


Imaginary Friend

by TheRegularWriter



Series: The Scientist [1]
Category: Undertale (Video Game)
Genre: Angst, Big Brother Sans, Blood and Injury, Body Horror, Brotherly Bonding, Car Accidents, Crying W. D. Gaster, Dadster, Everyone Needs A Hug, Family, Flashbacks, Friendship, Frisk lives with Goat Mom and the Skelebros, Gaster Needs a Hug, Gen, Good W. D. Gaster, Hurt/Comfort, Implied/Referenced Character Death, Lots of Crying, Major Character Injury, Near Death Experiences, Nightmares, Non-Binary Frisk, Non-Binary Monster Kid, Panic Attacks, Past Child Abuse, Post-Undertale Pacifist Route, Sad Gaster, Sad Sans, Sans Swearing, Suicidal Thoughts, Younger Brother Papyrus
Language: English
Status: Completed
Published: 2016-07-26
Updated: 2016-09-01
Packaged: 2018-07-26 19:52:00
Rating: Teen And Up Audiences
Warnings: Creator Chose Not To Use Archive Warnings
Chapters: 16
Words: 39,965
Publisher: archiveofourown.org
Story URL: https://archiveofourown.org/works/7587664
Author URL: https://archiveofourown.org/users/TheRegularWriter/pseuds/TheRegularWriter
Summary: <blockquote class="userstuff">
              <p>Frisk makes a new friend who cannot be seen by anyone else.</p>
            </blockquote>





	1. Friend

**Author's Note:**

> I'd like to note here that this fic is not related to "I Am Here". This was just an idea that popped in my head.
> 
> I apologize for any mistakes in the writing, such as the way I've written the characters in general.  
> Anyway, I hope you enjoy it!

Being stuck and alone in the Void was quite painful.

W. D. Gaster sighed while he fluctuated in the darkness of the Void, a dark, empty and cold dimension. He had been stuck in there since that terrible accident with one of his greatest experiments. While he was stuck, however, he at least could see what was happening in the real world. Nobody even noticed he was there, though; sometimes he even tried to talk to someone, but he was ignored. He even stopped doing that, after realizing how useless it was to call for help.

After he heard that the monsters were finally free, he lost his hope completely. He had always wanted to go to the surface, like any other monster. Even though he could visit the real world, he wouldn’t be able to breathe the fresh air from the surface. Even worse, he wouldn’t be able to cherish freedom next to his sons... actually, he was, but Sans and Papyrus wouldn’t even notice him.

Gaster sighed sadly. It had been such a long time since he left reality. He wondered if Sans and Papyrus ever thought of him. Probably not. They were only kids when the accident occured. He wouldn’t be surprised if they didn’t remember him.

He stared at the darkness. He would be lonely for the rest of his life. He kind of deserved it, though. He wasn’t a great father and he failed at giving monsters the freedom they all deserved. He could have destroyed the barrier years ago... but he _failed_.

He only wanted to make things right.

He wanted to be with his sons.

He wanted to go home.

Gaster cried. His tears fluctuated in the low gravity of the Void. He called for help, even though he knew how useless it was.

**_SOMEBODY..._ **

**_PLEASE..._ **

**_... I WANT TO GO HOME._ **

* * *

It was a beautiful day outside. Birds were singing, flowers were blooming. On days like these, Frisk enjoyed to sit on the grass, while watching the sunset. After spending a lot of time playing with other kids, they liked to have some alone time, aside from loving the sunset, specially with the beautiful landscape of the surface. Sometimes, Frisk watched the sun going down with Toriel, but she was busy at that moment. She had to do some school-related stuff. After that, she would bake a pie.

Frisk sighed happily, remembering the good life they had, after leaving the Underground. They were living with Toriel, Sans and Papyrus. Monsters were having a great life in the human world. Surprisingly – and thankfully -, humans were being receptive. Well, not all of them, though. Still, monsters were slowly getting accepted and were gaining their space.

The small child already planned what they were going to do at night. It was finally Friday; they could stay up until late. They thought of watching Mettaton’s TV show and then cartoons with Sans and Papyrus. They could imagine the trio having fun while eating butterstotch pie. They could tell that it was going to be a fun night.

When the sun was almost disappearing, Frisk was able to see the shining stars. The human sighed again. The world might not be perfect, but it was a wonderful one. Then, the child heard Toriel call their name in the distance, since she already knew they would be watching the sunset. She worried that Frisk could get lost in the forest near their home and cold, as the city’s weather wasn’t that hot, specially on that day. Frisk didn’t protest. They didn’t really like to wander around the woods at night, even if they liked to see the stars.

Frisk ran to the house, ready to give Toriel a hug. As they approached, they saw their Goat Mom (they loved calling her like that; she was very fond of that nickname) waiting for them, holding her own hands, which were covered by oven gloves. She gave Frisk a big smile when they reached her.

After they hugged, Frisk entered the house. Toriel closed the door. The child’s stomach rumbled when they smelled the butterstotch pie.

“I see you are hungry.” Toriel said. “You better eat something light. It will take a while to be ready.”

* * *

Gaster gave up on calling for help. Why was he even doing that? Nobody could listen to him, no matter how loud he screamed. He sighed. He stopped crying, after realizing that it was useless.

 ** _CRYING WILL NOT BRING ME BACK HOME._** He told himself, trying to stay calm.

He tried to stay positive. At least he was able to know what was happening in the real world, right? Because if he didn’t, he would be suffering even more. And thank goodness he was able to see Sans and Papyrus. Gaster smiled sadly when he imagined what they were probably doing at the moment.

He was very proud of them, despite Sans being lazy... His elder child did a great job taking care of Papyrus when he was younger – he was a great brother. Gaster would say the same for Papyrus.

Gaster promised to himself that he would _always_ be there for his sons, even after he disappeared.

Then... why the _hell_ was he not doing that at the moment?

He groaned. He was so focused on sadness that he didn’t even check Sans and Papyrus after going to the surface. He breathed heavily. He decided to stop focusing on himself to keep his promise. He wouldn’t break it. Not _again_.

Finally, he left the darkness and emptiness of the Void. He knew they wouldn’t stay in the Underground after the destruction of the barrier, though he didn’t know where they were. Thus, he ended up arriving somewhere close to Mount Ebott. The sky was black with several stars iluminating it. Gaster looked around. He found several houses and buildings in the distance. He... he couldn’t really walk, as he didn’t exactly exist. He had to fluctuate in order to move.

He fluctuated around... he only found grass, trees, some small animals... A few meters away from there, he found a nice, tidy and cute house. Curious, he approached it. He found several flowers standing in the garden, as well as hearing some voices coming from the house...

.... they were... familiar?

Gaster floated to the window’s direction. He gasped when he recognized the voices and the ones inside it. There they were: Sans and Papyrus. They were eating pie with a female goat and a little human child. Gaster could feel a warming feeling inside his heart after seeing how much fun his sons were having. The goat and the child seemed very nice. Actually, Gaster could tell he had seen the woman before. Her voice was familiar, too, but his memory failed. Same for the human... In any case, he just admired seeing his sons happy. The pie appeared to be delicious... too bad Gaster couldn’t even eat (he didn’t need to, for somewhat reason; after staying trapped in the Void, he didn’t need to sleep nor eat).

He paid attention to the conversation.

“SO...” Papyrus said, looking at the human. “HOW WAS YOUR DAY?”

The child answered, in an adorable voice:

“I played with my friends after school. We played the whole afternoon! We had a lot of fun!”

“That’s great, my child.” The woman said.

They were all happy, laughing with each other. Sans said some bad puns, making Papyrus annoyed, yet smile at the terrible joke. Gaster chuckled. Sans never changed... he made bad puns since he was just a little kid. Papyrus secretly loved them.

Gaster sighed. He was kind of happy, which was a strange feeling, specially when he spent most of his time in the Void, unhappy and lonely. Watching Sans and Papyrus happy was way better...

* * *

Frisk was almost sleeping. It wasn’t even midnight... They frowned a bit when they looked at the clock. They wanted to stay awake. Their favorite cartoons were about to air. Meanwhile, Mettaton’s show was still on TV. It wasn’t a new episode, but they liked watching some of them more than once.

Frisk glanced at Sans. He already fell asleep... they chuckled. Papyrus was still awake. He looked at Sans, too, and he rolled his eyes.

“TOO LAZY TO SEE METTATON... HMPF.” Papyrus whispered, making Frisk laugh a bit louder. It didn’t wake Sans up, though.

Papyrus noticed how tired Frisk looked.

“FRISK, YOU SHOULD GO TO BED.” He said.

Frisk whined. “Ugh, I don’t want to...”

“BUT YOU ARE TIRED! YOU NEED TO REST! AFTER ALL, YOU WAKE UP EARLY EVERY DAY BECAUSE OF SCHOOL.”

Frisk couldn’t deny that. They had that routine of waking up early... Convinced, they stood up.

“I’M GOING TO BED, TOO. I GOTTA CARRY SANS TO HIS BED...” Papyrus said, glancing at Sans, unimpressed.

Frisk gave a tired smile. “Good night.”

“HAVE A GOOD NIGHT, FRISK!” Papyrus smiled back.

The little child walked upstairs. They could hear Papyrus talking to Sans.

“ALRIGHT, SANS, LET’S GO TO BED.”

Sans groaned. “i like it here...”

“YES, BUT WHAT IS THE PURPOSE OF YOUR BED IF YOU DON’T SLEEP ON IT??”

With that, Sans stayed silent. Papyrus turned off the television and carried Sans to their room (they shared one). Frisk went to Toriel’s bedroom to give her good night. The door was open and she was still awake, reading a book.

“Hey, mom? I’ll go to bed now.” Frisk said.

Toriel glanced at the child, smiling.

“Alright, good night, dear.” She said, giving Frisk a good night kiss when they reached her.

“Night, mom.”

Frisk left Toriel’s room and entered their own. They put on their pajamas to go to bed.

* * *

Gaster had a sad smile on his face while he observed his sons sleeping peacefully. He tried to touch them... that didn’t work, obviously.

 ** _GOOD NIGHT, MY BOYS..._** He said, even though he knew that they wouldn’t listen.

He felt his eyes getting wet. It hurted. It hurted to not be there for his sons, when they didn’t even know he was next to them. He didn’t even... _exist_. And **_nobody_** remembered him. He promised he wouldn’t leave his sons, but... how was he going to help them if _he wasn’t even there_?

Gaster would be alone forever. Nobody would ever speak to him. There was no reason for him to be there anymore. Sans and Papyrus were doing well without him. They didn’t need him. They weren’t kids anymore. He was... he was wasting his time.

 ** _I... I DON’T WANT TO BREAK MY PROMISE._** He said to himself. **_BUT WHAT CAN I DO FOR YOU... IF I DON’T EVEN EXIST?_**

Gaster breathed heavily. Tears wouldn’t stop falling. He started sobbing and left Sans and Papyrus’s bedroom. He had to let them go. He was lost in another dimension, there was nothing he could do for them.

The lonely scientist sat on the floor of the corridor (somehow, he didn’t pass through the floor) and cried. He felt his heart ache.

* * *

Frisk took a while to get prepared. Finally, when they lied on the bed, they closed their eyes. They were about to sleep when they heard some strange noises...

They sounded like... sobbing.

Someone was crying.

Concerned, Frisk immediately opened their eyes. Who could be crying? They quickly stood up and walked to their room’s door. The sobbing was coming from the corridor. They opened the door. The other rooms' doors were closed. The child looked around, only to find someone... someone they had never seen before. The stranger was bald, had white skin. Their face was covered by their hands, which had holes. They wore a black overcoat. They sat on the floor, crying.

How did they get in there? How did they enter the house without making any noise? Frisk’s eyes widened. Before calling Toriel for help, they wanted to know who was that stranger, and why were they crying. The child slowly approached them.

“H-Hello?” Frisk whispered.

The stranger didn’t seem to notice them. They just kept crying.

“Mister...?” Frisk tried again. “A-Are you... okay?”

Suddenly, the unknown... person stopped sobbing. They anxiously looked at the child. They gasped, distancing themself. Frisk looked at them, confused, but with some concern.

 ** _WHAT THE.... A-ARE YOU.... TALKING TO... ME?_** The stranger asked. They sounded to be a man.

Frisk nodded, confused, but trying to be patient before screaming for help. The man didn’t seem to be dangerous, actually. Apparently, he was just a very sad man who needed some comfort.

“Who... who are you?” Frisk whispered.

The man took a while to answer. He looked very surprised after Frisk confirmed that they were talking to him.

 ** _I... I AM... W. D. GASTER._** He said, sounding nervous. He sniffled.

* * *

That was _extremely_ unbelievable.

That child was talking to him. They could listen to him. They could _see_ him. How was that even possible? Nobody else noticed Gaster’s presence. That didn’t make any sense!

“Why are you crying, mister Gaster?” The child asked, keeping their voice down. “And... and how did you get here?”

Gaster sniffled again. How would they explain the whole situation he had been through? How would he explain that he was stuck in another dimension because of an accident? It would be too much for a child.

But... they were genuinely concerned about him. Nobody knew how it was to be stuck in the Void. He had never opened up about it because nobody listened to him. He didn’t want to throw the opportunity of talking to someone away.

He sighed. **_IT... IT IS A LONG STORY, CHILD..._**

The little one approached him more, curious, yet somehow scared. Well, who wouldn’t be scared of an unknown man who just showed up in their house?

* * *

Gaster had... a strange appearence. He had two scars on his face. His eyes were big and had white pupils... Suddenly, Frisk thought of Sans. Both had white pupils. Well, that was just a coincidence.

The child waited for him to speak. He seemed anxious to tell them.

 ** _LOOK..._** He began. **_IT IS VERY COMPLICATED, IT IS FINE IF YOU DO NOT UNDERSTAND, BUT..._**

**_WELL, YOU SEE... I WAS A SCIENTIST. THE ROYAL SCIENTIST OF THE UNDERGROUND. MANY YEARS AGO, I CREATED A MACHINE THAT WOULD FREE THE MONSTERS. HOWEVER... IT WENT ALL WRONG. THE MACHINE WAS DANGEROUSLY UNSTABLE AND IT... IT ABSORBED ME. THEN IT BROKE. HOWEVER, FOR SOME REASON, I HAVE SURVIVED..._ **

**_... BUT I... I WAS SENT TO ANOTHER... DIMENSION, THE VOID. A DARK, EMPTY DIMENSION. SINCE THEN, I HAVE BEEN STUCK IN THERE. I CAN STILL SEE WHAT HAPPENS IN THE REAL WORLD, BUT... NOBODY CAN SEE ME, OR LISTEN TO ME. I HAVE BEEN FEELING QUITE LONELY._ **

Frisk wasn’t confused at all. They had seen some weird stuff in the Underground, after all... It did surprise them, though, that he was still alive, somehow. Besides, nobody else even noticed his presence.

**_I... I JUST CAME TO YOUR HOUSE TO... TO SEE MY SONS._ **

Sons? Was he talking about...

“You mean... Sans and P-Papyrus?” Frisk asked.

Gaster nodded sadly. **_THAT IS RIGHT._**

Frisk’s eyes widened. They had a father? It sort of made sense, considering that they were brothers, but... none of them have ever mentioned Gaster before. Not as Frisk remembered.

 ** _BUT... THEY DON’T EVEN KNOW I EXIST..._** More tears fell from his eyes. **_THEY DON’T KNOW I’M HERE. NOBODY DOES._**

Frisk looked at him with a sad face. He was just a lonely, lost man, who wanted someone to talk to, who wanted to be there for his sons.

“I... I’m sorry.” That’s all Frisk could say at the moment. They really were sorry.

 ** _DO NOT WORRY, CHILD... W-WELL, I BETTER LEAVE NOW._** He said, standing up. **_I DO NOT BELONG TO THIS WORLD ANYMORE._**

Frisk didn’t want him to leave. He was really sad and lonely. They didn’t want him to suffer like that. The scientist was ready to leave when Frisk blocked the way, even though he could just pass through them.

“D-Don’t go, mister Gaster!” Frisk said, trying to keep their voice down. “I don’t want you to be alone.”

**_I... I WILL BE ALRIGHT, HUMAN._ **

“No, you won’t... You will be even more lonely. I don’t want that for you.”

Gaster looked away. **_HUMAN..._**

“Stay. I want to help you.”

**_YOU CANNOT HELP ME, CHILD..._ **

“I... I can be your friend, mister Gaster.”

He looked at them with surprise. **_WHAT?_**

“Isn’t that what you want? I mean, you said you were lonely and nobody knew you existed. But I know. I’m here, talking to you. I... I don’t want you to leave. I don’t want you to suffer.”

* * *

That child... they were so sweet. They were concerned about him. They wanted him to _stay_.

**_HUMAN, I..._ **

“Please... don’t you want someone to talk to?”

Of course he did. All he wanted was someone who he could open up to. He was so lonely, he was neglected by everybody. He... he only wanted a friend, someone to trust.

**_YES, BUT..._ **

“I will be your friend, mister Gaster.” The child said, with a sad smile on their face. “Please, don’t go.”

He sighed. He was... he was feeling better, actually. He didn’t feel his heart aching that much anymore. The presence of the child was helping him a lot.

Somehow, he reminded of Sans and Papyrus, when they were only kids. He remembered when they wanted to cheer him up when he wasn’t feeling well... Gaster had done the same thing: distance himself. Not in an aggressive way, but... it made their sons think that they were _annoying_ him. That was the worst thing he could’ve ever done to them. He loved them so much... how dare he do that to people who cared so much about him?

He wouldn’t make the same mistake. That child genuinely cared about him. They wanted to help him, just like what Sans and Papyrus would do for him. He sighed sadly. He managed to give them a smile. Remembering his mistakes was something really painful. He was about to cry again...

**_OKAY, I... I WILL STAY HERE, CHILD._ **

The human’s smile lost a part of the sadness. They yawned, suddenly.

**_OH, YOU MUST BE VERY TIRED... YOU BETTER GO TO BED._ **

“Yeah, I will go to bed now... You can come with me to my bedroom, if you want.”

The child opened their bedroom’s door. They waited for him to come in. A little hesitated, he entered the room.

**_ARE YOU SURE YOU WANT ME HERE?_ **

“Well, only if you want to.” They said, giving a tired smile.

Gaster shrugged. The child laid on their bed, breathing deeply.

**_HAVE A GOOD NIGHT, HUMAN._ **

The child chuckled quietly before closing their eyes. “Good night... and, uh, my name is Frisk, by the way.”

He smiled at them. Frisk quickly fell asleep. They were very tired... Gaster felt a bit clumsy by staying in that child’s bedroom. They didn’t even know him that much, yet they were willing to help him, to be his... _friend_. What a friendly and sweet child. It reminded him of Papyrus... The younger skeleton loved to make friends, and was also willing to helping others.

Gaster smiled sadly while looking at Frisk. Then he sighed. He wasn’t sure what he could do. All he did was lay on the floor. He didn’t do anything but that. At least he had some company... He was glad that Frisk was there, knowing that he existed.

Gaster closed his eyes.


	2. Talk

Frisk woke up and yawned, looking around to find Gaster.

“Good morning, mister-“

He wasn’t there. Frisk hoped he didn’t leave while they were asleep. Though he could have gone anywhere he wanted. The child put on their tiny slippers, walking around the room.

“Where are you?” They asked.

Then, Gaster showed up by passing through the wall. Frisk sighed, smiling at him. “Oh, there you are.”

**_GOOD MORNING, FRISK. I WAS ONLY... WATCHING SANS AND PAPYRUS. THEY ARE ALREADY HAVING BREAKFAST WITH THE WOMAN._ **

“Oh, already? I hope I’m not late!”

Frisk was about to run to the kitchen until they stopped in the middle of the way, remembering the fact that Gaster was in their house.

“Um, mister Gaster?” Frisk called him, keeping their voice down. “Would you like to go to the kitchen with me? I mean, you can't really eat anything, right? But if you don't want to be alone, you can come."

 ** _OF COURSE._** Gaster smiled.

Frisk went downstairs. Gaster walked (actually, he fluctuated) behind them. The two headed to the kitchen. Thankfully, Toriel was still preparing the breakfast table. Most things were there, though. Sans and Papyrus were waiting for everything to be ready. The taller skeleton noticed Frisk and gave them a big smile.

“GOOD MORNING, FRISK!” He said. “I WAS ABOUT TO GO TO YOUR ROOM TO WAKE YOU UP, BUT THIS TIME YOU DID IT BY YOURSELF!”

Frisk looked at Gaster. Nobody seemed to notice him. He sighed sadly.

“DID YOU SLEEP WELL??” Papyrus asked.

“Yes, of course."

The child sat on one of the empty chairs. They glanced at Gaster and gave them a fast smile before facing their friends and eating breakfast.

* * *

Gaster didn’t say a thing during the breakfast. He was lost in his own thoughts while Frisk talked to Papyrus and the goat woman. Sans was still kind of sleepy and didn’t really say much during the entire time. Frisk gave some small and fast smiles to Gaster when nobody noticed. He was still glad that at least one person acknowleged his existence. He thought he would be lonely forever stuck in the Void... However, he wondered if anyone would judge Frisk in case they heard the child talking to an invisible man... Maybe people would think he was an imaginary friend. The problem was that some people could be really judgemental.

He'd better talk about it to Frisk later. He wasn't in a hurry, though.

* * *

"Do you have any idea of how long you've been in the Void?"

Gaster and Frisk walked around the garden. The child was careful to not step on the flowers. Gaster didn't have to, as he didn't really exist. He could hear birds singing in the distance. That place was quite comfortable and relaxing.

Gaster sighed before responding.  ** _I CANNOT REALLY SAY FOR HOW LONG... THOUGH, WHEN THE ACCIDENT OCCURED, SANS AND PAPYRUS WERE STILL KIDS._**

Frisk's eyes widened. "I see... and there's literally nothing in the Void?"

Gaster shook his head.  ** _DARKNESS IS MY ONLY COMPANY IN THAT DIMENSION. ALSO, THERE'S NO GRAVITY. IT FEELS LIKE YOU ARE FLUCTUATING IN SPACE, BUT... THERE ARE NO STARS, PLANETS NOR GALAXIES. IT IS COMPLETELY EMPTY._**

Frisk stared at the flowers. They were trying to imagine how it felt like to be stuck in the Void. Gaster really wouldn't like Frisk to experience that horrible prison of loneliness and despair.

 ** _AND WHAT ABOUT YOU, FRISK?_** Gaster asked. He was very curious about Frisk's life with his sons and the woman, besides the fact that monsters were living in the human world now. **_HOW IS YOUR LIFE UP HERE?_**

"It's great, actually." Frisk said, smiling at the scientist. "Toriel is a great mom. Sans and Papyrus are amazing friends, too."

**_TORIEL...?_ **

"Yeah, the... goat." Frisk said.

**_... OH, IS SHE... THE QUEEN?_ **

Frisk nodded. "Yes. I never thought she had been one when I first saw her, though."

 ** _SHE IS SO... DIFFERENT NOW._** Gaster murmured. He was kind of surprised, but at the same time, not really. He knew that he had seen the goat woman before. It just surprised him that she looked so different. 

**_AND WHAT ABOUT KING ASGORE?_ **

"They're still not together..." The child shrugged. "I don't think they would go back to be a couple, though. At least Toriel is friends with him now."

**_YES, I KNOW WHAT HAPPENED... THE WHOLE STORY INVOLVING THE FIRST FALLEN HUMAN, RIGHT?_ **

Frisk nodded.

**_ANYWAY... WHAT ABOUT SANS AND PAPYRUS? WHAT ARE THEY DOING NOW?_ **

"Papyrus is still taking cooking lessons, but from someone else. He's improving a lot. He will probably work at some restaurant in the future. Sans is a comedian at a place I forgot the name... but he still takes some breaks to take a nap."

Gaster shook his head, chuckling.

"Oh, and Toriel is a teacher now." Frisk added. "I study at the school where she works."

**_THAT IS NICE._ **

Frisk continued talking about other monsters - most of them Gaster couldn't quite remember, or didn't even know - and how they were doing in the human world.

* * *

"SANS, YOU ARE SLEEPING ALREADY?!"

Sans was napping on the couch right after breakfast. Papyrus, as always, was pissed at the laziness of his brother. He had a job and still took several naps during the day...

"pap, i'm tired..." Sans mumbled.

"YOU ARE ALWAYS TIRED!!"

"awwwww, paps, please, five more minutes..."

"ALRIGHT!" Papyrus rolled his eyes, leaving Sans on the couch.

Toriel chuckled while she washed the dishes. Those two were hilarious, though they could get on her nerves sometimes. They could be really immature... Heh, they were brothers, after all. Toriel was getting used to it.

While washing the dishes, she could see the garden by the window. Toriel found Frisk walking outside. She smiled, but as she paid more attention to the child, she noticed that... they were talking... to themself? That wasn't strange. Toriel talked to herself sometimes. However, Frisk appeared to be... talking to _someone_. Like, they said something, waited for an answer and then said something else. They even laughed at some point. Toriel continued on washing the dishes while wondering if Frisk had a imaginary friend or something. That wouldn't be bad, clearly. Children usually had imaginary friends, even if they were older.

After finishing, some footsteps could be heard from outside. It was probably Frisk. She heard them say something. Apparently, it wasn't directed to her.

"I'm going to watch some cartoons, want to join me?" They asked. After a while, before opening the door, they said, "Oh, great! I bet you're going to like them!"

The child opened the door and seemed surprised to find Toriel in the kitchen.

"Oh, hey mom!" They said. Toriel noticed some nervousness in their voice tone.

"Hello, Frisk."

"Er... I'm gonna watch TV."

Before leaving the kitchen, Toriel asked: "Frisk, who were you talking to?"

"Oh, nobody."

Frisk gave her a nervous smile before going to the living room. Were they ashamed of having an imaginary friend? They shouldn't, in reality. Toriel would talk to them about it later. She still had to do some stuff on that day.

* * *

Frisk was heading to the couch but found Sans sleeping on it. He was snoring.

"Oh, Sans." Frisk murmured.

They looked at Gaster, who simply shook his head. The two jumped when they heard Papyrus's angry voice coming from upstairs. They heard his aggressive footsteps approaching.

"SANS!!! OH MY GOD, YOU TOLD ME YOU WERE GOING TO STAND UP AFTER FIVE MINUTES!" He yelled.

Sans's face was covered by the couch, so his response was in a muffled voice: "i know, i was about to do it..."

"IT HAS BEEN MORE THAN FIVE MINUTES, SANS!! OKAY, THAT'S IT, I'M CARRYING YOU TO THE BATHROOM SO YOU CAN TAKE A SHOWER!"

Sans whined in protest. That didn't stop Papyrus to take him off the couch. "YOU LAZYBONES! I CAN'T EVEN IMAGINE WHAT WOULD YOU DO WITHOUT A COOL BROTHER TO TAKE CARE OF YOU!"

Frisk and Gaster shook their heads, trying not to laugh. Frisk then turned on the television. Gaster was able to sit on the couch. He felt very indifferent about it, of course. It sucked that he couldn't feel the comfort of it. The child glanced at the kitchen, finding Toriel cleaning it. Frisk sighed, remembering that their Goat Mom questioned if they were talking to anyone. Frisk didn't know if they should tell her they had a new friend. They trusted Toriel, but they didn't feel really comfortable with revealing Gaster's existence.

Meanwhile, Gaster curiously watched the TV. The human TV was very different from the monster one. Maybe not that much, but they weren't the same. They assumed that the void scientist was enjoying it. He even laughed at some parts of a TV show they were watching. Frisk wanted to watch some cartoons, but they let Gaster have some fun; he probably hadn't naturally  _laughed_ in decades.

It was nice to see Gaster happy. Frisk wished to see him like that more often.

* * *

That Saturday was nice. Frisk spent a long time with Gaster. They either watched television or simply talked when nobody was near. When they weren't alone, Frisk would just talk to Papyrus, who cooked some spaghetti after taking Sans off the house. Gaster proudly watched his son cook for a while.

At the end of the day, the two watched the sunset together. Gaster was quite impressed with the beautiful view.

 ** _IT IS... VERY STUNNING._** He said.

Frisk smiled. "I always watch the sunset, when possible. It's very relaxing."

Gaster nodded.

 ** _I HAVE NEVER SEEN THE SUNSET BEFORE._** He admitted.  ** _I WAS BORN IN THE UNDERGROUND._**

Frisk lost a bit of their smile. "How was your life before... the accident?"

Gaster sighed, taking a while to answer.

"O-Oh, sorry, you don't need to talk about it." Frisk said, regretting the question.

**_IT'S ALRIGHT, I WILL TELL YOU._ **

He sighed once again and began talking:

 **_LIKE I SAID, I WAS THE ROYAL SCIENTIST. I MARRIED A BEAUTIFUL WOMAN AND HAD TWO CHILDREN. MY WIFE, UNFORTUNATELY, PASSED AWAY... THE ONLY GOOD THINGS I HAD IN MY LIFE THEN WERE SANS AND PAPYRUS. I HAVE DONE EVERYTHING TO GIVE THEM A GOOD LIFE, WHICH MADE ME WORK EVEN HARDER AFTER MY WIFE WAS GONE. BUT THEN_ ** **_I STARTED BEING SO FOCUSED ON WORK THAT I DIDN'T REALLY GIVE THEM MUCH ATTENTION. I BARELY SPENT TIME WITH THEM. WHEN I WAS IN A BAD MOOD, I USUALLY TOLD THEM TO LEAVE ME ALONE..._ ** **_I WASN'T A GOOD FATHER._ **

**_MY LIFE WASN'T REALLY THE BEST, IN GENERAL. I SPENT HOURS WORKING ON THE LABORATORY EVERY SINGLE DAY, MAKING SEVERAL EXPERIMENTS. IT WAS NERVE-WRACKING. IF IT WASN'T FOR SANS AND PAPYRUS, THOUGH... IT WOULD'VE BEEN WORSE._ **

Frisk could see he was about to cry.

**_I WISH I COULD HAVE BEEN A BETTER FATHER TO THEM. I PROMISED THAT I WOULD ALWAYS BE BY THEIR SIDE, EVEN AFTER BEING SENT TO THE VOID, BUT... I REALIZED THAT I AM WASTING MY TIME. THEY DON'T NEED ME ANYMORE. THEY PROBABLY WOULDN'T LIKE TO SEE ME AFTER EVERYTHING I HAVE DONE TO THEM._**

"Don't say that! I think they would be glad to see you again." Frisk assured him. "I mean, you deeply cared about them and did everything to offer them proper conditions and-"

 ** _YES, BUT... I HAVE NOT GIVEN THEM ENOUGH LOVE AND AFFECTION._** He sighed sadly.

Frisk sighed too. They had a feeling that Sans and Papyrus didn't hate him. They just knew it, but Gaster didn't believe.

"But... they never gave up on you, right?" They asked.

Gaster had a moment of realization. His eyes widened, but then the sadness and regret took control.

**_I DID NOT DESERVE, THEN..._ **

"Gaster..."

 Frisk then said something they never thought they would mention it ever again.

"I would've really liked to have a father who would do everything to give me a good life."

Gaster, curious, looked at the child.  ** _WHAT DO YOU MEAN?_**

"Toriel is my mom now, and she's the best, but... I've never had a **father** that cared about me." Frisk admitted. "You know... before I fell into the Underground. My real parents weren't... great. They were very mean to me, specially my father."

Gaster felt bad for them, as Frisk noticed it by his expression.

"Actually, they're the reason why I ran away from my past home." They said. "I fled to the forest and I found the Mount Ebott. I curiously explored it, but then I fell... It was the best thing that happened to me, to be honest."

**_I AM SORRY ABOUT YOUR PARENTS._ **

"It's okay. At least I found great friends and a fantastic mom." Frisk said, smiling, despite remembering their mean parents. "You are a way better father than my real one. You shouldn't say you're the worst."

Gaster didn't answer.

"You may have not spent much time with them, but I don't think Sans and Papyrus wouldn't be happy to see you." Frisk said.

**_BUT I MADE THEM FEEL LIKE THEY WERE ANNOYING ME... I SHOULD HAVE NEVER DONE THAT._ **

"I understand, but, just so you know... I think you already made it clear to them that you cared about them, which is why they were always there for you even if you distanced yourself."

Gaster stayed silent. He looked away and stared at the sun going down, thoughtful. The sky was getting darker already. Frisk looked at the stars for a while before talking to their new friend.

"We better go inside." Frisk said. "It's getting dark and Toriel's going to be worried about me."

He nodded, following the child, who was walking in the direction of the house.

**Notes for the Chapter:**

> Heh... I just wanted to write Frisk and Gaster talking, and you know... opening to each other.  
> I also had this sad headcanon that Frisk's biological parents were abusive and they were the reason why the child climbed the mountain. Sorry ;v;


	3. Better

Toriel prepared the table for dinner. She looked at the window to see if Frisk was still outside, but then the door was opened. The child arrived, already giving Toriel a big smile.

"There you are." She said, smiling back. "I was busy and I haven't really seen what you have done the entire day. What did you do today?"

"Ah, y'know... I watched TV, talked to Papyrus, walked around the garden, watched the sunset..."

"You just... stayed home then?" Toriel asked.

"Yes, pretty much."

Toriel felt a bit suspicious. Frisk wasn't someone who liked to stay home the entire day, specially on weekends. They usually called some of their friends to play, or hung out with Papyrus, Undyne and Alphys. The child still seemed happy. Somehow nervous... Toriel wondered if that had to do with the supposed imaginary friend.

"Can I talk to you about something?" She asked.

"Sure, about what?" Frisk sat on an empty chair. Toriel approached the table, but didn't sit on another chair.

"Earlier today, I noticed you were talking to... someone." She said, going straight to the point.

"Really? Oh, I was... talking to myself, actually."

Toriel sighed. "Frisk, don't be ashamed of telling me. I know you weren't talking to yourself." With that, Frisk cleaned their throat, nervously. They didn't know what to say and looked at the wall. It seemed like they were waiting for an answer from... someone.

* * *

For real: what should they say? They hated to lie, specially to Toriel. She was their Goat Mom, she was the best. She didn't deserve a lie after everything she had done for the child. But Frisk knew Toriel wouldn't believe in them if they said they were talking to a real man. She would probably go along and _pretend_ Gaster was real by thinking he was only an imaginary friend.

Frisk glanced at Gaster, who didn't say anything. Then they faced Toriel again. She held her own hands and waited for an explanation.

"Okay, I... I have made... a friend." Frisk admitted.

Toriel's concern faded a little. "Really?"

Frisk nodded, smiling nervously. "Yeah, but, uh... nobody else can see him."

"Oh. Anyway, I'm glad you have made a new friend. What's his name?"

Frisk glanced at Gaster again, looking at him like they were saying "should I reveal your name?". He responded with a sad shrug, as he knew nobody would even remember him if they heard his name.

"His name is, uh... Gaster." Frisk said. Toriel didn't seem to record this name.

"That's a nice name. Did you spend some time with him today?"

"Yes, yes, we had a lot of fun today."

Toriel smiled but sighed. After a while, she said: "You know... you shouldn't be afraid of telling me you have made a friend. I can see you are very happy with that and I'm glad for you."

Frisk looked away. "I know, sorry."

"Don't apologize... I just want you to know you can tell me anything and that you shouldn't be afraid, okay?"

The child smiled at Toriel. She was simply the best mom they could have ever asked for.

"Thanks." They said.

"Oh, you should take a shower... dinner will be ready soon."

"Okay, mom."

Toriel smiled again. Frisk smiled in return before going upstairs, arriving quickly at the bathroom. Gaster stayed in the corridor.

"I'm taking a shower, so, uh... you can watch TV with Papyrus or... maybe just wait." The child suggested. Gaster nodded in response.

Frisk closed the bathroom's door, leaving Gaster alone.

* * *

That Mettaton had an interesting design...

Gaster watched the Mettaton's TV show with Papyrus, while the skeleton didn't have any idea that his father was sitting right next to him. The robotic TV star was posing dramatically over... everything. He didn't even know what was that program about. Gaster didn't see much appeal from it, except for Mettaton's design; that robot had some nice legs... Despite the show not being that pleasant, Papyrus still enjoyed it.

"OH, HE'S SUCH A DRAMA QUEEN." Papyrus said, rolling his eyes with a smile. "BUT HIS SHOW IS THE BEST!!"

Gaster chuckled. He was only watching a lousy TV show because Papyrus was happy. He liked how his son reacted to what was happening in the program.

"OH MY GOD, HE DID NOT DO THAT!" Papyrus yelled after Mettaton's grumpy assistant say something very mean. The scientist could hear Toriel giggle at Papyrus while she was making dinner. Gaster just gave him a warming smile.

* * *

"She thinks you're an imaginary friend... I'm sorry for not telling her that you're real. She wouldn't believe me..."

After dinner, Frisk and Gaster were in the child's bedroom. He didn't seem to mind about Frisk not revealing his existence to Toriel. Instead, he gave the child a small smile.

**_DO NOT APOLOGIZE, FRISK. I UNDERSTAND. AND... I GUESS YOU HAVE DONE THE RIGHT THING. EVEN I CANNOT UNDERSTAND HOW I SURVIVED A GRAVE ACCIDENT... ASIDE FROM LIVING IN ANOTHER DIMENSION. IT WOULD BE REALLY CONFUSING IF YOU TRIED TO EXPLAIN._ **

Frisk sighed, staying silent for a while. Then they said: "I wish I could help you get out of the Void."

**_I APPRECIATE IT, BUT... YOU KNOW HOW IT IS. HONESTLY, THOUGH, BEING YOUR FRIEND IS ALREADY HELPING ME. THANK YOU._**

Frisk couldn't help but smile. They loved to help people.

"Thanks." They said.

The two stayed in silence for a while. Gaster looked around the room while Frisk sat on their bed, staring at their own feet. Then someone knocked on the door.

"FRISK? ARE YOU AWAKE??" Papyrus asked.

"Yes, why?"

"CAN I COME IN?"

"Sure!"

Papyrus opened the door, sneaking his head.

"I WANTED TO KNOW IF YOU'D LIKE TO, UH... WATCH CARTOONS?" He asked. "THERE'S GOING TO BE A MARATHON!"

"A marathon?? Of course! I won't miss it for anything in the world!"

"GREAT! I WILL GET SOME POPCORN!"

Papyrus went downstairs. Frisk almost rushed to the stairs when they looked back at Gaster.

"You coming?" They asked.

**_I'D RATHER... STAY HERE, IF YOU DON'T MIND._ **

"Oh, I don't mind at all." Frisk smiled and murmured: "I'll be back later... hopefully, I won't sleep on the couch."

Gaster smiled.  ** _HAVE FUN._**

The child then ran downstairs. They could smell the popcorn coming from the kitchen.

* * *

Gaster felt like he needed some alone time. He was very thoughtful after what Frisk told him earlier - about Sans and Papyrus being sure he loved them since they were always there for him. That made sense... But Gaster didn't deserve to have wonderful sons like them.

How would they react if they saw him again? Would they be happy? Would they be sad? Or even angry? Gaster still didn't doubt that they probably hated him, but after opening up to Frisk, his view on that was changing. Slowly, but changing for the better.

Gaster really appreciated Frisk for being a great friend; they were very smart, despite still being a kid. He also appreciated the fact that Frisk trusted him enough to tell him about their past parents. He was still surprised - in a positive way - at the sudden change in his life. He made a friend and wasn't alone anymore.

He sighed happily. For the first time in forever, he didn't feel the sadness and the regret taking complete control over him anymore.

**Notes for the Chapter:**

> This chapter turned out to be shorter than the previous ones... oh well. ._.
> 
> Anyway, what do you think about the story so far?


	4. Memory

A few days passed, and Frisk and Gaster's friendship developed. They talked about several topics; the examples would be the human world, as Gaster didn't know much about humans, Sans and Papyrus, their experiences and likes and dislikes. It already looked like they were good old friends. Gaster was feeling way happier after being friends with Frisk. He finally had someone to talk to. The child appeared to be happy, too. They liked being friends with him and did their best to make him feel better about himself, after everything he had done.

Although Frisk usually talked to Gaster when they weren't around anyone, their friends had already seen the child talking to the "invisible man" in a few occasions. Toriel sometimes asked Frisk about Gaster, but, of course, being oblivious to the thought of him being real.

"Did you play with Gaster today?" Toriel asked. Frisk just realized that she probably didn't imagine Gaster being an adult... usually the questions involved child things (which, of course, did not imply that Gaster wouldn't play with a child, as he was a father, after all).

"Yes, we had a lot of fun while, um... watching cartoons."

Sans and Papyrus didn't know about that until Toriel revealed them that their friend was sitting on the couch while Frisk watched the TV one day.

"FRIEND? WHAT FRIEND?" Papyrus asked.

"It's their friend Gaster." She said. "He's sitting next to them, so I wanted to make sure you won't sit on him."

"OH... OH, I GET IT! OKAY, I WON'T SIT ON HIM!" Papyrus winked at Toriel.

Toriel sighed, relieved. At least Papyrus understood what she meant. With that, she went back to the kitchen. Frisk glanced at Sans and... they noticed something strange about his expression after Toriel said... that name. Frisk didn't say anything to Gaster, who was distracted by the TV at the moment. Frisk wondered if Sans remembered Gaster... He suddenly wasn't smiling anymore, like he usually did. Papyrus noticed that and touched his shoulder, with a concerned face.

"SANS, ARE YOU ALRIGHT?" He asked.

"i... i'm fine, pap. i just... need to go to the bathroom."

Sans left the living room, going upstairs. Papyrus sighed.

"OH BOY... HERE WE GO WITH SANS NOT TELLING ME ANYTHING." He murmured to himself, but Frisk was able to hear that.

The child looked at Papyrus sadly. The skeleton looked back and then he went back to his cheerful personality.

"ANYWAY, WHAT ARE YOU AND YOUR FRIEND WATCHING?" He asked.

Papyrus sat on the other corner of the couch, aware of Gaster's presence on the middle of it. With that, the trio watched TV for a long time on that day.

Meanwhile, at school, some of Frisk's friends had seen them talking to Gaster (who, of course, could not be seen). Some of them thought it was weird but didn't say anything about it, while others didn't care at all.

In general, nobody judged Frisk for having an "imaginary friend". They all went along with it.

* * *

Papyrus just finished cooking some spaghetti for dinner.

"DINNER IS READY!" He said.

Toriel could see the spaghetti from where she stood. She was able to smell it.

"Oh, I already like the smell." She said. "I bet the taste is even better."

Papyrus put the spaghetti on four plates, giving two of them to Sans and Toriel. Sans started to chuckle.

"how do you say, papyrus?" He asked.

"WHAT?"

"you know...  **bone**  appetit?"

Toriel giggled, while Papyrus groaned loudly, facepalming with both hands.

"AGHHHH!" He yelled.

Meanwhile, Toriel took one bite from the spaghetti.

"Mmm, Papyrus, this is really good!" She said. "I see you have been improving even more lately."

Suddenly, Papyrus completely forgot about Sans's terrible pun and blushed lightly at Toriel's compliment on his cooking.

"REALLY? AWW, THANK YOU, LADY ASGORE!" Papyrus said.

Toriel rolled her eyes. " _Toriel_."

"WELL THEN... THANK YOU, LADY TORIEL."

Toriel shook her head in disapproval, but she couldn't hide the smile. She continued to eat the spaghetti. The skeletons started eating, too. Papyrus glanced at the empty chair where Frisk was supposed to sit. Even after he yelled that the dinner was ready, Frisk didn't come.

"WHERE'S FRISK?" Papyrus asked.

"They are in their bedroom, I think." Toriel answered. "They started being alone in there for a while... they're probably talking to Gaster, their imaginary friend."

Sans suddenly frowned. Papyrus noticed that again, but he didn't say anything. He knew that Sans wouldn't tell him what was wrong. Toriel, however, asked him anyway, as she didn't really know how mysterious Sans used to be.

"Are you alright, Sans?"

"i'm okay."

 _NO, YOU AREN'T._  Papyrus thought.

Toriel stood up and said: "Well then... I better call Frisk, or else their food will cool."

She left Sans and Papyrus in the kitchen and headed to Frisk's bedroom. Before knocking on the door, however, she heard Frisk talking to their imaginary friend.

"I can't believe it! They really were terrible when they were kids."

* * *

Gaster was talking about Sans and Papyrus to Frisk, when they were only children. According to his memories, the skeleton brothers haven't changed anything, except for the fact that Papyrus wasn't so confident about himself. When they were little, they still teased each other, while still caring a lot about each other... actually, they were way worse.

"They stayed almost the same, honestly." Frisk said. "They still tease each other."

 ** _OH, THESE BOYS..._**  Gaster laughed.  ** _THEY GAVE ME A LOT OF WORK..._**

Frisk heard a knock on the door. Then it was opened by Toriel.

"Frisk? I don't think you have heard Papyrus say that dinner was ready, so..." Toriel said.

"Oh! Sorry, I didn't hear that. I'm coming."

Frisk stood up and gave a fast smile to Gaster before following Toriel to the kitchen.

"DIDN'T YOU HEAR ME CALL YOU, FRISK?" Papyrus asked.

"No, sorry about that."

"WELL, IT'S OKAY! AT LEAST YOUR SPAGHETTI IS STILL WARM!"

Frisk sat on the empty chair. They ate the spaghetti, which was quite delicious.

* * *

_They're probably talking to Gaster, their imaginary friend._

Gaster.

That name gave Sans a bad memory. A memory that he hadn't remembered in a while.

Everytime he heard that name, it came back to his mind.

That one memory...

* * *

_"Dr. W. D. Gaster, y-your father... he suffered an accident with one of his experiments and... I... I am sorry."_

_Sans was a little kid again. A monster - another scientist - visited his house to let him know about the tragic accident that his father had suffered. The little skeleton looked at the man in complete disbelief. Sans understood what he meant._

_"w-what...?" He said, quietly._

_He felt like he was punched in the stomach, despite not having one. His dad had promised him he would be back home. He promised that he would take his sons outside to play in the snow. He promised they would build a snowman and make snowballs to throw at each other. He promised that they would finally spend time together._

**_He promised._ **

_"S-SANS?"_

_Sans saw Papyrus behind him. His little brother was really worried. Sans really hoped that he hadn't heard what happened to his father._

_"WHAT... W-WHAT HAPPENED TO DADDY?" He asked._

_"papyrus..."_

_Papyrus approached Sans and the scientist._

_"Your father... he... he suffered an accident." The adult said._

_"BUT... H-HE WILL BE OKAY, RIGHT?"_

_Sans's heart broke completely. His brother was so innocent... The scientist sighed sadly, shaking his head._

_"I am deeply sorry." He said._

_Papyrus's eyes widened and they formed tears._

_"NO... NO..."_

_Sans hugged his brother tightly. Papyrus sobbed on his shoulder, saying "no!" multiple times. Sans cried quietly._

_"i can't believe he's gone..." Sans whispered._

* * *

Sans shook his head, trying to take that off his mind. That memory still haunted him; he didn't get over his father's death. He tried to stay cool. He was having dinner with his friends and his brother and he really didn't want to be seen crying. He absolutely hated to talk about that topic.

He stayed quiet the whole time. Nobody really said anything about Sans being silent. He took a long time to finish eating while everyone else already finished their food.

Toriel was washing the plates when Sans finally finished his dinner. He then put his plate on the sink.

"i can help you with the dishes." He said.

"Thank you, but don't worry about that." Toriel gave him a worried smile.

He could see that she did notice that he wasn't feeling well, but she didn't ask anything. Sans appreciated that and smiled in return, then leaving the kitchen.

* * *

Sans told Papyrus he would tell him a story. He was very excited, already on his bed, waiting for his big brother. As soon as Sans arrived, Papyrus felt his excitement grow more.

"STORY TIME!!" He said.

Sans gave him a weak smile. Papyrus quickly lost his joy as he noticed that Sans wasn't as happy that day as when he was going to tell his brother a story.

"SANS... SERIOUSLY, WHAT HAPPENED?" Papyrus stood up to sit on his bed, while Sans simply fell on his bed, groaning quietly.

"SANS."

"bro, i'm just tired."

"EVEN IF YOU ARE TIRED, YOU ALWAYS TELL ME A STORY! I KNOW THERE'S SOMETHING BOTHERING YOU. I NOTICED THAT EARLIER!"

Sans stayed silent. Papyrus stared at him and sighed deeply.

"SANS, WHY WON'T YOU TELL ME ANYTHING?" Papyrus asked. "YOU ARE ALWAYS HIDING THINGS... I AM YOUR BROTHER, I WANT TO HELP YOU!"

Sans sighed again. "it's... it's stupid."

"IT'S NOT STUPID IF IT MATTERS."

Sans finally had the gut to look at his brother. Papyrus went to his messy bed, sitting on it. Sans sat on it, too, to give him space.

"YOU CAN TELL ME, BROTHER." Papyrus said.

"i know, it's just... i don't really like to talk about it. but... okay, i'll tell you."

Sans turned his gaze to the floor, seeming ashamed.

"it's... it's all because of... frisk's new... friend." He admitted. "i mean, when toriel said his name, i... i had that terrible memory again."

Papyrus knew what he meant. The human's new imaginary friend was called Gaster. He had remembered his father when he heard the name, but he hadn't felt that bothered.

"i suddenly... turned back into a kid and... i just... remembered that guy telling me about... the accident." Sans continued. "ugh... everytime i hear that name this memory pops in my mind and i feel really..."

Papyrus felt bad for him. Sans still didn't get over his father's death, while he, at least, knew how to deal with it. Sans didn't like to remember that terrible day, and he didn't react well about it.

"OH, SANS..." Papyrus said.

Sans sighed. "why does frisk's friend have to be called... gaster?"

"SANS, YOU KNOW THAT CHILDREN CAN INVENT ANY NAME POSSIBLE FOR THEIR IMAGINARY FRIENDS."

"i know but... why... gaster?"

Papyrus gave him a hug. Sans didn't return it right away. They didn't say anything for a long time.

"I MISS HIM..." Papyrus finally said. "I KNOW HOW IT FEELS."

Sans sighed in response. He tightened the hug a little.

"i miss him so much, pap..." He admitted.

"ME TOO... BUT THERE'S NOTHING WE CAN DO ABOUT THAT, SANS. WE NEED TO MOVE ON."

* * *

He tried so hard to move on. He really did. But that memory would always be there, waiting for its next appearence. It would always haunt him. Sans, however, didn't want to talk about that anymore. He was deeply bothered about it. He let go of Papyrus.

"thanks, bro." He said. "i"m feeling better now..."

Papyrus smiled, being oblivious of the lie his brother told him. "YOU CAN ALWAYS COUNT ON ME, SANS."

"i know."

"THEN DON'T BE AFRAID OF TALKING TO ME ABOUT THINGS THAT BOTHER YOU, OKAY?"

Sans nodded in response.

"WELL, YOU BETTER GET SOME SLEEP... GOOD NIGHT." Papyrus said.

The taller skeleton went to his bed. Sans wouldn't let his little brother sleep without a story! He would do it, no matter how tired he was.

"hey pap?"

"YES?"

Sans gave him a happier smile. "wanna hear a story?"

Papyrus's face quickly lightened up, nodding.

"get comfy, bro." Sans said.


	5. Don't Forget

Gaster was still impressed at the fact that humans and monsters were studying in a school together. He never thought that day would ever come... In any case, he appreciated the school (the one where Frisk studied) for having students from both races, studying in the same classrooms, and also its educational system. The teachers were very kind; Gaster was particularly fond of Toriel.

During recess, Gaster smiled as he watched Frisk playing with their friends. He liked to see that Frisk had both human and monster friends whom they got along very well. They were all having a lot of fun, and played several things, such as tagging and hide and seek.

The recess then finished and Frisk reached Gaster, who was a bit distant from where most children stayed.

"You okay?" They asked. "You usually don't stay this far from me."

_**WHY YES, I JUST... PREFERED TO STAY A BIT DISTANT FROM CHILDREN... I DON'T FEEL VERY COMFORTABLE AROUND MANY PEOPLE.** _

"Oh, it's okay, I understand." Frisk smiled. "Now come on, class will start soon."

The child ran to the interior of the school, but not too fast so that Gaster could reach them. When they reached it, Frisk stopped running and walked normally. Gaster saw some of their friends leaving the bathroom. They were a bit older and taller than Frisk, and were all humans. They noticed the child and looked at each other, but then they left. Frisk didn't notice that. They were a bit distracted. Gaster fluctuated next to the other kids, listening to their conversation. He didn't like to hear others' conversations, but he had the bad feeling that they were talking about Frisk.

"Frisk is so weird..." One of them whispered. "I mean, they're really smart, but like, they have an imaginary friend..."

"I know, right? Besides, they treat him like he's real! Everyone who has an imaginary friend knows that they aren't talking to a real person!"

They were gossiping about Frisk... that wasn't a nice thing to do. It was rude to talk about someone that way, specially when it was about a great friend like Frisk. By the way, Gaster looked back to his friend. When they noticed him, their face frowned with confusion. The scientist fluctuated back to them.

"What were you doing there?" They asked.

_**NOTHING...** _

Gaster cleared his throat, giving them a smile. Frisk stared at him for a while. He glanced at the other kids and... they were looking at them, frowning, too.

 ** _WELL, WE SHOULD KEEP MOVING, FRISK. YOU CLEARLY WOULD NOT LIKE TO BE LATE, AM I RIGHT?_ ** Gaster suggested, smiling.

Frisk didn't say anything else, being convinced by Gaster's suggestion. The other kids walked away after the two stopped talking.

* * *

At home, Frisk was doing their homework, once in a while asking for Gaster's help in some questions. He easily answered them. With that, Frisk finished the work in a short period of time.

Gaster still felt kind of guilty after Frisk's friends were saying how they were weird. He didn't want other people to judge Frisk and distance from them because of their conversations with him. He only wanted a friend without prejudicing them.

He honestly didn't know if Frisk would even care about that... if not, then he really was an _idiot_ for caring about other people distancing from Frisk.

"Hey, Mr. Gaster?" Frisk called him.

Lost in his own thoughts, he tried to smile, but failed.

_**YES, FRISK?** _

Frisk frowned as they noticed that Gaster wasn't really that happy anymore.

"Are you okay?" They asked.

_**AH, I WAS JUST... LOST IN MY OWN THOUGHTS, BUT I AM FINE.** _

Frisk didn't seem convinced, but didn't say anything about Gaster acting weird. He was kind of relieved, though. He didn't feel like he should tell what their friends were saying about them. Frisk was happy, then why should others' opinions matter?

* * *

"Where is Sans, Papyrus?"

Papyrus was watching the TV when Toriel called him. The two of them were alone in the house, as Frisk went to play with that Monster Kid and their friends, and Sans left the house and probably went to Grillby's.

"NOWHERE TO BE SEEN..." Papyrus sighed. "HE DOESN'T WORK AT THIS TIME, SO HE JUST LEFT THE HOUSE... WELL, HE'S PROBABLY AT GRILLBY'S. HE ALWAYS GOES THERE, SPECIALLY WHEN... HE'S UPSET."

Toriel looked at him with concern. She did record that Sans hasn't been really fine lately.

"Is he still upset? And about what?"

"YES... WELL, HE WAS VERY BOTHERED BY THAT IMAGINARY FRIEND'S NAME, YOU KNOW?"

"Oh, you mean Gaster?"

"YES... IT'S A LONG STORY. I TALKED TO HIM AND HE TOLD ME HE WAS FEELING BETTER, BUT... HE DOESN'T SEEM BETTER TO ME."

Toriel looked away, gazing at the television. She had a bad feeling about Frisk's friend, for some reason. The child seemed happy, but... there was something about their friend that seemed... off.

"TORIEL? YOU SEEM... WORRIED." Papyrus said when he looked at her again. "IS IT ABOUT SANS?"

"Well, yes, Papyrus, but... it's about Frisk's friend, too." She sighed. "There's something about Gaster that... concerns me, for some reason."

"OH, REALLY?"

Toriel sat on the other corner of the couch, facing Papyrus.

"I mean... I'm glad that Frisk is happy, they are really having a good time with their imaginary friend, but..." She sighed. "I-I have a bad feeling about him."

"WHY?"

"I don't know, I... I listen to Frisk talking to him. There's something strange about their conversations. I can't really explain why I think that."

"I DON'T THINK YOU NEED TO WORRY." Papyrus gave her a smile. "IT'S QUITE COMMON FOR CHILDREN TO HAVE IMAGINARY FRIENDS AND THEY HAVE DIFFERENT CONVERSATIONS, TOO!"

Toriel tried to smile back, but she didn't really believe in Papyrus. Aside from Frisk's conversations with Gaster being strange, they weren't comfortable with talking about him. It felt like they were hiding something, and that concerned her. What if something was wrong? What if Frisk had a problem and created an imaginary friend for comfort?

"But... Frisk doesn't like to talk about him." Toriel said. "They feel nervous and uncomfortable when I suddenly show up while they're talking to him."

"YOU KNOW, LADY TORIEL, SOMETIMES CHILDREN FEEL A BIT EMBARRASSED OF TALKING ABOUT THEIR IMAGINARY FRIENDS... THERE'S NOTHING TO WORRY ABOUT THAT! THAT'S COMPLETELY NORMAL!"

She sincerely hoped that Papyrus was right, because that bad feeling in her gut was telling her otherwise. Maybe she was just overreacting. She should respect that Frisk wasn't fond of talking about Gaster. It was just odd that they were embarrassed about something... Frisk wasn't like that. But hey, they were growing up, and there would be changes in their behaviour. She shouldn't be surprised, should she?

* * *

_why does that still bother me?_

_why do i care so much about an imaginary friend's **name**?_

Sans was at Grillby's, like always. As a comedian, he didn't really need to work every single day, which allowed him to take many breaks. Although Grillby's bar was in the human world, there were barely any humans; monsters usually stayed there, which was kind of funny, considering that humans loved grease. They would certainly enjoy that place, wouldn't they?

The skeleton just drank tons of ketchup while his thoughts destroyed him. He was so bothered about Frisk's imaginary friend that even he thought he was being completely dumb, but he couldn't help it. He would never hear his dad's name without recording that horrible memory. Sometimes he wished he could erase his mind.

_ugh, snap out of it. he's named gaster, so what? just get over it, dummy._

He wouldn't get over it, though.

* * *

Frisk was asleep when Gaster just walked around their room. He did several things when his friend was sleeping, as he couldn't sleep. That night, the scientist did nothing but walk in circles, at least until he heard a door opening downstairs. It was already dawn, and Gaster wondered who would be arriving at that time. Turned out that it was Sans. He seemed tired, physically and mentally. He sighed deeply and threw himself in the couch. Gaster fluctuated towards him. He really wished he could speak to his son, to know what he had been up to, and what would be bothering him.

"god, i'm so stupid." Sans whispered to himself, staring at the ceiling. "why do i even care about that?"

Gaster looked sadly at Sans. He stood next to him, even trying to touch him, but his hand passed through his skull.

 _ **WHAT IS THE MATTER, SON?**_ Gaster asked, aware that Sans wouldn't listen to him.

Sans groaned quietly, covering his face with his hands.

"why can't i move on?" He asked. "why can't i just... let him go?"

Let him go?

What could that possibly mean? Who was he talking about?

Gaster didn't find out the answer, since Sans didn't say anything else. Instead, he went straight to his bedroom after a while, throwing himself on his bed again. Papyrus was asleep and didn't notice his brother entering the room.

Gaster stayed in his sons' bedroom, noticing that Sans didn't sleep at all. He just stared at the ceiling, sometimes glancing at Papyrus to make sure he wasn't awake.

 _ **OH, SON, I WISH... I WISH I COULD HELP YOU WITH WHATEVER YOU ARE GOING THROUGH.**_ Gaster said.

Suddenly, Sans said, breathing heavily:

"i miss you, dad."

Gaster's eyes widened. Did he know he was there? Was he talking to him?! The scientist almost screamed, but realized that Sans was just talking... to himself. His left eye turned blue and he magically made a card appear on his hand. Gaster gasped when he recognized it.

 _That_ card...

The card contained a poorly drawn picture of three people - Sans, Gaster and Papyrus. It was made by Papyrus years ago, on Father's Day. The scientist cried and his heart broke a little. Sans remembered him... and Papyrus probably did, too.

Sans stared at the card for a while. Gaster then noticed that there was something written on it. He recognized the handwriting; it was Sans'. Though he did not remember anything written on the card.

Written on it...

" **don't forget.** "

Sans sighed sadly. He seemed like he was about to cry. He hugged the card, closing his eyes.

"i will never forget you." He whispered.


	6. Lie

Sans stayed awake the whole night. All he did was lie on his bed and let the memories of his father haunt him, since he was too dumb to let him go. Meanwhile, Papyrus slept peacefully, having no idea of how terrible his brother felt.

In the morning, Papyrus woke up cheerfully, like every other day. He yawned and said: "HERE COMES ANOTHER DAY FOR THE GREAT PAPYRUS!"

Unlike his brother, Sans was tired and angry, and upset, and sad, and... basically, he was feeling terrible.

"GOOD MORNING, SANS!" Papyrus said, happy. "COME ON, LET'S GET UP-!"

Papyrus was suddenly quiet. Sans didn't even look at him, he only stared at the ceiling. He must have been looking awful if it made his brother quiet.

"SANS, DID YOU SLEEP WELL?" Papyrus asked.

"i'm okay, pap."

"BUT YOU LOOK AWFUL-"

"papyrus, i'm _okay_!" Sans interrupted, sounding annoyed.

* * *

Papyrus shrunk out of fear. He had never seen Sans in that state before. He knew something was up with him, but for some reason, he was afraid of asking Sans what was wrong. His brother sounded so grumpy, he felt like he would piss him off if he asked that at the time.

"go downstairs." Sans said, breathing heavily. "i'll be up in a minute."

Papyrus sighed sadly, losing his happiness. "OKAY."

He went downstairs, only to find Toriel in the kitchen. The table was all ready, but she still waited for everyone to arrive. She smiled at Papyrus before she noticed that he wasn't happy like usual.

"Papyrus? Is there something wrong?" She asked.

"SANS IS PISSED... I DON'T THINK HE HAD A GOOD NIGHT. HE SOUNDED REALLY ANNOYED WHEN I TRIED TO TALK TO HIM..."

"He might just be in a bad mood." Toriel assured him. "Maybe he will get better later, then you can talk to him."

"I'M NOT QUITE SURE ABOUT THAT... HE NEVER TELLS ME ANYTHING." Papyrus sighed. "I DON'T THINK HE EVEN TRUSTS ME."

He looked away, gazing at the food on the table. Toriel stared at him with a concerned look, not saying anything. The skeleton only ate some bread and drank milk, and didn't say anything else.

* * *

It honestly hurted a little to see Papyrus sad like that. He didn't do anything wrong, he only wanted to help Sans. Papyrus actually felt guilty for asking Sans what was wrong, and Toriel could see that on his face. She wanted to comfort him, but Papyrus probably wouldn't like to talk about it.

Toriel sighed and told him before standing up: "I'll call Frisk."

Papyrus nodded sadly in response.

* * *

"Sans seems so... upset."

After breakfast, Frisk and Gaster went outside the house again. The two of them sat among the beautiful flowers while the brighting sun iluminated Frisk, while the light simply passed through Gaster. He didn't even have a shadow...

"Papyrus told me he was in a bad mood. And he didn't even come to eat breakfast." Frisk said. "Well, he's not, you know... happy all the time, but... I've never seen him like that."

Gaster sighed. He knew why Sans was so upset: he missed his father. He didn't get over the fact that Gaster was gone.

_**HE MISSES ME.** _

Frisk looked at him with a certain surprise. Gaster had always told them that nobody remembered him, so it would be obvious that they would be shocked. "Really?"

_**YES... HE DIDN'T GET OVER... MY "DEATH". HE MISSES ME SO MUCH. I NEVER THOUGHT HE WOULD EVEN REMEMBER ME.** _

"Wow.. he must miss you a lot, mister Gaster. Not only him, but also Papyrus, but I think he deals with it better than Sans."

Gaster nodded sadly. With that, the two stayed quiet for a while. Gaster was back at feeling guilty for abandoning his sons and not letting them know he loved them when he had the chance. He felt like garbage, and his heart, which was recovering thanks to Frisk, broke once again. He wanted to come back but he couldn't, and at the same time he didn't want to. Not after everything he had done. He didn't deserve sons like Sans and Papyrus, nor a friend like Frisk.

_He deserved to be stuck in the Void._

Gaster wanted to cry, but he didn't want to do that in front of Frisk. He didn't want them to worry. They were already doing so much for him, even if he didn't deserve it. He simply sighed.

"Are you okay?" They asked.

_**I AM ALRIGHT... I JUST- NO. NO, I DON'T KNOW. I DON'T KNOW HOW I SHOULD FEEL.** _

Frisk didn't say anything. They didn't understand how he felt, but they still looked at him with concern.

"Want to talk about it?" Frisk asked.

_**I'M AFRAID I'M NOT IN THE MOOD TO...** _

"It's okay. But you can always count on me."

Gaster stared at the horizon, sighing once again.

_**I KNOW.** _

* * *

They were outside with their friend again. Toriel watched them by the kitchen's window. She really didn't want to worry about Frisk having an imaginary friend. It was normal, it should be normal, but there was just something wrong. She knew it, and she didn't know why she had that strange feeling of concern. Papyrus had already told her that it was completely okay, but he didn't convince her.

 _How silly of me... I shouldn't be worrying so much about this._ She thought. _There's **nothing** wrong with Frisk, nor their imaginary friend. Why do I feel there is?_

She did worry a lot... But could she really help it? Even after what had happened... to her past children?

Ever since that tragedy, Toriel had become even more protective of anyone she took care of - the other fallen humans, Frisk... even Sans and Papyrus. She cared so much, and worried so much... she didn't need to.

"hey tori."

Oh, speak of the devil. A long time has passed since breakfast, and Sans has just arrived. He was smiling, but Toriel did know he wasn't okay. He looked exausted... yet he was... being kind to her. Strange how he was annoyed at Papyrus.

"Good morning, Sans." Toriel said, not sounding very happy.

Sans noticed, but he looked away.

"sorry, i lost breakfast, didn't i..." He said. "i was really tired... i didn't sleep well."

"I know."

"um, you know?"

"Yes, Papyrus told me." Toriel approached the short skeleton.

Sans sighed, staring at his feet.

"What's wrong, Sans? Be honest." Toriel said. "Papyrus told me you were annoyed at him for trying to help you."

Suddenly, Sans's eyes widened. "what?"

Toriel sighed and continued: "It's exactly what you heard. And I know he was telling the truth. Seriously, Sans, what's wrong? What's so bad that you can't even tell your own brother?"

"it's a long story... i don't like to talk about it."

"Does it have to do with him?"

Sans sighed. "no."

"Then why don't you tell him?"

"he... he wouldn't understand, and... it's just..."

"You don't trust him?"

Sans remained silent after that question. Toriel even glanced at the living room and the stairs, secretly glad (somehow) that Papyrus wasn't home. He had left the house to visit Undyne and Alphys, and he would be back later.

"Be honest with me, Sans." Toriel said, seeing that Sans wouldn't answer.

* * *

That wasn't true, Sans did trust Papyrus. He was his brother, he would always be there for him. Sans could always count on him.

The problem was that... he didn't expect Papyrus to understand that Gaster's death still haunted him. That didn't mean that Papyrus didn't miss Gaster; of course he did, but Sans... Sans would never get over his death.

Papyrus wouldn't understand.

...

"i trust him, tori." Sans answered after staring at the floor for several minutes. "it's just... i don't think he would understand."

Toriel breathed heavily. "Sans... you don't trust him. If you did, you _would_ expect him to understand. You would tell him."

"toriel, that's not true."

"Yes, that is." She said. "You know I'm right, Sans."

Sans stayed quiet. He... he didn't want her to be right. He did trust his brother. But a part of him knew Toriel was saying the cold truth: **he didn't trust him at all**.

"no, no, that... that isn't true." Sans continued denying. "he's my brother, i do trust him, i..."

Toriel didn't say anything, but still gave him a look of disapproval. She knew she was right... and she was.

Sans sighed deeply. "welp... i... i... i-i need to go to the bathroom."

"Sans-"

Sans transported himself out of the kitchen with his magic before Toriel could say anything else. He soon arrived at the bathroom, and locked its door.

* * *

Toriel had one more thing to be concerned about: Sans.

He hated to talk about what was bothering him. He didn't want to admit that he didn't trust Papyrus. Toriel didn't really blame him, as she didn't know what was upsetting him, and she had kept many secrets from Frisk herself... But it broke her heart. She couldn't help but think about how would Papyrus react if he was there hearing the entire conversation. He just wanted to help Sans, and his older brother didn't even trust him.

What could she do, though? Sans would never tell her what was happening, he would simply avoid his problems by transporting himself to somewhere else or something. Also, she didn't feel like she should tell Papyrus about Sans not trusting him.

 _I'm not the one who should tell Papyrus about this._ She thought. _Sans should be honest with his feelings._


	7. Sorry

Days had passed, and things hadn't got really better. Sans was still annoyed and he and Papyrus became kind of distant. Toriel became more concerned about Frisk, as the child wasn't playing with their friends anymore. Most of them started to treat them as a weirdo for having an imaginary friend, as their conversations were very... different. Frisk wanted to prove people that he was real, but no one believed in them. Gaster just felt worse by thinking about how much Sans was suffering because of him, aside from his friend being rejected by most of their friends; at least there was still that Monster Kid, but Gaster couldn't help the pessimistic feelings. He knew it wasn't his fault that other people judged Frisk, but... he felt guilty, somehow. Frisk only talked to him now, after realizing how their other friends were stupid and judgemental.

_You are a terrible father. You abandoned your children._

_You had the responsibility to free all monsters, but you failed._

_You deserve to be imprisoned in a dimension of eternal darkness and despair._

**_You deserve it._ **

Gaster wanted to stop those voices inside his head. He tried to stay cool, but he failed. Meanwhile, by his side, Frisk was drawing something with crayons and pencils, but they told him to not peek until it's done. Gaster stared at the wall, not breathing well. He overthought every single mistake he had made and the punishment for them.

He... he just couldn't be there anymore. Not after everything he had done. He didn't deserve a friend like Frisk. The child was oblivious to his mistakes, they insisted that he did have a good side. Because of him, Frisk was being more alone than before. The child obviously was keeping this from their mother and their skeleton friends. That was really concerning, but there was nothing Gaster could do, since Frisk was sure that nobody would understand.

_Not only you are a bad father, but you are also a bad friend to Frisk._

_What kind of friend would make one distance oneself from others?_

_Why do they even like you?_

_You disgusting piece of garbage._

**_You deserve to die alone._ **

Gaster shook his head. After spending decades inside the Void, he could have gone crazy. Somehow, he could hear some distorted and creepy voices destroying his self-esteem, making him feel a lot worse about himself. He didn't want to listen to them because there were people who genuinely cared about him. He wasn't a bad person... was he?

_You should leave._

_You should leave and never come back._

**LEAVE ME ALONE!** Gaster thought.

He sobbed quietly, with tears forming on his eyesockets. He hoped that Frisk didn't hear him crying again. He didn't want to be heard anymore...

_It will be better for everyone._

_It was already fine._

_Your sons were glad without you._

_Frisk was doing fine without you._

_Now, thanks to you and your selfishness, the child is alone._

_Sans is suffering and has distanced from his brother._

**_This is all your fault, you idiot._ **

He fought against himself. Although he didn't really feel anything physical as he was stuck in another dimension, he could feel himself being stuck in the darkness again. The voices were louder, they were yelling at him, telling him horrid things.

And... they were all  _true_.

It was sad, but it was true. Everyone had done fine without him. Now that he was back, everything just got worse. He could feel his heart break completely again. He could feel his body getting heavier and his head aching a lot as well. The voices just got louder and louder by the time. He sobbed loudly.

_You are worthless._

_You are pathetic._

In the middle of a sea of distorted voices, he could hear Frisk's voice echoing in his mind.

_M-Mister Gaster?_

He opened his eyes, jumping out of fear. He was back at Frisk's bedroom. The child was terrified and deeply worried. They... they were about to cry. Gaster wondered what could have they seen that scared them so much.

"W-What happened?" Frisk asked. "Oh my god, you were... you looked so...  _terrifying_."

* * *

Frisk couldn't even believe what they had just witnessed. Gaster's body... was horrifying at some moment. It started melting, rivers of tears fell from his eyes. God... what had happened? Was that... normal for someone who was stuck in another dimension?

 ** _SOME... SOMETIMES CREEPY THINGS HAPPEN TO MYSELF._** Gaster attempted to explain.  ** _THE VOID... THE VOID IS A PLACE THAT CAN DO ANYTHING TO MY PHYSICAL FORM. I DON'T REALLY KNOW HOW, BUT..._** He sighed, not even finishing the sentence.

"Oh god..." Frisk whispered.

They were almost crying. It was really frightening to watch their dearest friend in that state. Gaster gasped, shocked that Frisk was so scared of him.

 ** _O-OH NO, FRISK..._** Gaster said, sounding regretful and ashamed.  ** _D-DON'T CRY! I... I AM ALRIGHT! MY B-BODY IS... MY BODY IS NORMAL NOW! SEE?_**

He forced a smile. That didn't make Frisk feel better... That smile just emphasized that Gaster was  **not**  okay at all.

"Gaster... a-are you really okay?" They asked.

Gaster sighed, losing his smile.

 ** _FRISK..._** He said.  ** _I... I AM SORRY FOR... EVERYTHING._**

"What?"

**_I MADE YOU... I MADE YOU DISTANCE YOURSELF FROM YOUR FRIENDS... YOUR FAMILY... I... I JUST MADE EVERYTHING WORSE._ **

"W-What do you mean?" Frisk asked. "T-That's not true! That's not your fault!"

**_IT IS TRUE, FRISK. EVERYTHING WAS FUNCTIONING WELL WITHOUT ME. NOW THAT I CAME BACK... EVERYTHING JUST WENT BAD._ **

Frisk didn't understand anything he was talking about. Wasn't he happy with their friendship? He was getting better, wasn't he? Gaster was honest with his feelings, he had told the child he wasn't feeling like garbage anymore.

"Mister Gaster, no... don't say that..." They said. "You are a great friend, I love spending time with you!"

 ** _FRISK, I LOVE IT, TOO... BUT I DON'T DESERVE SOMEONE LIKE YOU._** Gaster turned his back to them.  ** _I... I DON'T DESERVE FRIENDS AFTER EVERYTHING I HAVE DONE._**

"That's not true! You are a great person! You are a great and dedicated father, and... you're my  _best_  friend!"

* * *

Best friend?

Gaster didn't record having a  _best_  friend in years...

Frisk was being serious. They... they really cared about him. But... he couldn't do that to them. He didn't deserve such love from a great friend like them.

 ** _FRISK... YOU... YOU REALLY MATTER TO ME._** He said.  ** _OUR FRIENDSHIP IS THE BEST THING THAT HAPPENED IN MY LIFE EVER SINCE I WAS SENT TO THAT HORRIBLE DIMENSION. HOWEVER... I... I DON'T DESERVE THIS. I DON'T DESERVE YOU. I DON'T DESERVE SANS AND PAPYRUS._**

"S-Stop saying that! You're not bad! You may have made mistakes, but everybody does!"

Gaster chuckled darkly. Frisk always saw the positive side in others, even the ones who did unforgivable things. They... they really were like Papyrus. What an innocent, naive child... If only they truly knew what had the scientist done. Gaster didn't have the courage of telling them his mistakes.

He let his wife die; nothing he had done to cure her from her disease worked. He neglected Sans and Papyrus, barely spent time with them and... treated them like they were just a burden in his life, when they really weren't. He had failed at freeing monsters, he had broken everyone's trust. He had disappointed everyone. He had had one job, and he failed.

 ** _OH, CHILD... YOU REALLY HAVE NO IDEA WHAT I HAVE DONE._** Gaster said, almost bursting in tears.  ** _YOU WOULDN'T FORGIVE ME._**

Frisk looked at him with disbelief. That look of theirs broke his heart even more. He didn't want to leave them. Their friendship was so important to him. He had never met such a great friend like them. He would never forget that child.

He... he deserved to go back to the Void. And he was willing to do that, if it meant that everything would be back to normal, and if that would make everyone feel better and just return to their ordinary lives. Gaster breathed heavily.

 **YOU KNOW WHAT TO DO.** He thought.  **YOU HAVE TO DO THIS... FOR THEIR SAKE.**

He made his way to the bedroom's wall.

 ** _THANK YOU FOR EVERYTHING, FRISK. YOU REALLY ARE A GREAT FRIEND._** He said.  ** _I... I WILL LEAVE NOW._**

"W-What? A-are you going back...  **there**?"

Gaster took a while to nod in response. He looked at Frisk, whose eyes were wet.

"N-No! Don't go!" They yelled. "W-Why are you doing this?!"

 ** _IT'S FOR YOUR OWN GOOD... IT WILL BE BETTER FOR EVERYONE._** Gaster sighed. He started crying, too...  ** _I AM SORRY._**

"No..."

Gaster turned his body to Frisk.

 ** _I HAVE TO GO NOW._** He said.  ** _I... I HOPE YOU UNDERSTAND._**

"N-No..."

He gave them a sad smile.

**_GOODBYE, FRISK._ **

He closed his eyes. With his forces, he transported himself back to where he belonged to.

He opened his eyes. The old darkness was the only thing there. He sighed sadly.

 **IT WAS THE RIGHT THING TO DO.** He thought.

* * *

He was... gone.

"M-Mister Gaster?" They called him, even though they knew, deep inside, that he wouldn't come back.

No answer.

Frisk was really upset at him leaving like that. They thought he was okay. They thought they were helping him... but they didn't. They didn't help him get out of the Void. He just... lied to them. They wanted to be mad at him, but... they just couldn't. After remembering what Gaster had said about being stuck in the Void, they understood why he had such a pessimistic view of himself. He was just regretful. He wasn't the same as before.

Instead of being angry at Gaster, they felt guilty. Guilty for not truly helping him.

Frisk made their way back to their table. Lying on it was that drawing they were going to show Gaster: a picture of the two, with the words "Best Friends Forever!". The child sighed, crying quietly.

"I'm sorry." They said. "I'm sorry for not saving you."


	8. The Hidden Machine

What a great day to attend to a parent-teacher conference... Toriel was very busy doing house chores and, even though Papyrus was there to help her, she realized she would be late. She was in such a rush that she didn't even bother taking a shower and only put some nice clothes on. That would be enough. Then, Toriel left some food for Sans, Papyrus and Frisk to eat while she was gone.

Finally, everything was all set. Toriel sighed, relieved. She was feeling a bit exhausted after doing so many things in a day, but hey, that was her job, after all.

Sans went to Grillby's and didn't arrive yet. Papyrus was taking a shower (Toriel knew this by hearing him sing loudly), and Frisk... actually, she didn't see them the whole day. Knowing that Frisk would be outside to watch the sunset, Toriel made her way to the door to the back of the house. She opened it, expecting Frisk to be outside... However, they weren't there this time. Toriel blinked, confused. Frisk went there every single day to watch the sunset and they would stay a little longer just to see the first stars to shine in the sky. Toriel then wondered where would they be, as they didn't go out to play with their friends... she ended up concluding that Frisk would be in their bedroom, after all.

Toriel went back inside, walking to Frisk's bedroom. She found the door closed, and no noise could be heard.

* * *

Staring at the drawing of them filled Frisk with pure sadness and guilt. But what else could they do? They weren't in the mood to do _anything_ but just... see Gaster again, which would never happen again. Because of that, Frisk couldn't help but just... look at the Gaster they had drawn. He was smiling, he was happy... Frisk seriously thought he was feeling better about himself, but the complete opposite had happened.

Well, Gaster sure had been happy with Frisk around, as he had told them how much their friendship mattered to him. He cared about Frisk so much... that he only went back to the Void for Frisk's life to go back to normal, when they clearly didn't want him to leave. He didn't believe he was a good person. God, Frisk just remembered how awful the Void sounded by hearing Gaster's experiences in it. No wonder why the scientist had changed so much...

Frisk sighed sadly. If only Gaster saw how great he was, despite making mistakes...

If only Frisk could bring him back...

"Frisk, are you in there?" Toriel spoke from the outside, knocking on the door.

Frisk quickly hided the drawing by putting some blank papers and crayons over it. They dried their wet face and attempted to smile.

"Yeah, come in." They said, trying to sound happy.

Toriel opened the door, already giving them that lovely Goat Mom smile. That warmed Frisk's heart a little, but it wasn't able to fully recover from the pain of Gaster's suffering.

"I just wanted to let you know that I will be gone for a while." Toriel said. "I think I have already told you about the parent-teacher conference tonight, right?"

Frisk nodded in response.

"Well then, I have left some food for you and the boys to eat." Toriel continued. "There's a butterstotch-cinnamon pie awaiting at the kitchen." She winked at Frisk, who gave a weak smile as a response. Toriel's smile quickly faded.

"Are you alright?" She asked.

"Yes, I'm just... bored. I didn't really know what to do the entire day."

"I see you have been drawing?" Toriel glanced at Frisk's desk.

"Well, I tried, but... nothing came out." Frisk sighed.

* * *

Toriel frowned, knowing that Frisk was lying. She noticed how they weren't okay or just "bored". They were having an issue, but they wouldn't tell her.

"Frisk, I... I would like to talk to you when I get back, alright?" Toriel told them, serious.

Frisk nodded, appearing to be nervous. Toriel sighed. If she wasn't in a hurry, she would talk to them right away.

"Be good, okay? Oh, and let Sans and Papyrus know about the food." Toriel said, then kissing Frisk's forehead.

"Okay, bye, mom."

"Goodbye, my child."

Toriel glanced at Frisk before walking away.

* * *

"OHOO! GOOD AS NEW!"

Papyrus was all clean, after a great shower. His battle body was looking great, like usual. Its greatness was so strong, it reflected on the mirror. Papyrus proudly posed at the mirror before going downstairs. The living room was strangely silent, as Frisk would usually be watching TV at that time, specially on Fridays. The skeleton looked around, but then Frisk arrived.

"OH, HELLO THERE, FRISK!" Papyrus said, happily. "HOW ARE YOU DOING?"

Frisk shrugged. "Fine, I guess. Oh, I wanted to let you know that Toriel will be out for a while and she left some food for us at the kitchen."

"GOLLY! WE SHALL EAT SPAGHETTI AND SOME TASTY PIES, AND WATCH CARTOONS!"

Frisk would usually be as excited as Papyrus, but... they didn't seem very hyped. Papyrus frowned, sadly remembering that his brother was in the same state, except that he was irritated and silent most of the time, unlike Frisk, who was actually _smiling_ (it was a weak smile, but it still counted as a smile, right?) at Papyrus.

"ARE YOU OKAY?" He asked.

Frisk sighed. "It's complicated, and... it's kind of hard to explain, and... I'm not... really in the mood to talk about it, sorry."

"NO, IT'S ALRIGHT, FRISK... BUT STILL, YOU CAN OPEN UP TO ME." Papyrus smiled sadly. "FEEL FREE TO TALK TO ME ANYTIME!"

"Thanks."

Papyrus did feel a bit better that he wasn't annoying Frisk by asking them about what was bothering them. He soon noticed that his brother wasn't around yet. Sans would probably be at Grillby's-

Oh well. The door opened. Sans has finally arrived. There was some ketchup on his face. Yep, he had definitely been at Grillby's...

"oh, hey guys." Sans said, not sounding happy, not smiling either.

"Heya." Frisk answered, giving a weak smile to him.

Papyrus couldn't even face his brother... Instead, he simply stared at his feet. 

"whatcha' doing?" Sans asked.

"Just... talking."

Papyrus nodded, confirming Frisk's response.

"are you... guys okay?" Sans asked, sounding somehow... worried.

 _OBVIOUSLY NOT, SANS._ Papyrus thought.  _NOT WHEN YOU ARE ANNOYED BY MY PRESENCE..._

"Well, not much." Frisk admitted, sighing, while Papyrus remained silent. Sans didn't comment on it, though.

* * *

Frisk felt somehow bad for the two. They were sure that Sans was still bothered by their imaginary friend's name, while Papyrus was sad that Sans wouldn't tell him anything and would simply snap at him when he tried to help. It was a bit saddening to think that they were distant because of _Gaster_...

Should they tell Sans and Papyrus about Gaster? Like, he was their _father_. They had the right to know what was going on, but Frisk feared their reaction, specially when Sans felt extremely uncomfortable with anyone mentioning Gaster. They probably wouldn't believe in the child, but... Frisk had to try, right? Though, by thinking about it, they mentally apologized to Toriel, who had just wanted to help them. They promised they wouldn't lie to her anymore.

 _Welp, there goes nothing..._ Frisk thought, breathing deeply.  _They need to know, even... even if they don't believe in me. I have to try._

They really wanted to help Gaster. If necessary, they would do pretty much anything.

Sans glanced at Papyrus for a second before staring at the floor. The tall skeleton sighed.

"I... I BETTER GO CHECK ON THE FOOD." Papyrus said, already walking to the kitchen's direction.

"Papyrus, w-wait, I-"

Papyrus stopped in the middle of the way and looked at Frisk.

"Okay, I... I have something to tell you." They said. "Both of you, actually."

"WHAT IS IT?" Papyrus walked back to Frisk and Sans.

Frisk glanced at the roof, for some reason... They sighed again.

_I'll do this for you, mister Gaster. I promise I'll get you out of the Void._

"Look, i-it's about... my friend." Frisk said. "You know... my friend Gaster?"

Sans frowned and Papyrus sighed sadly by finally looking at his brother.

"He's... okay, I know it sounds crazy, b-but..." Frisk attempted to tell the truth. "Ugh, h-he's real, okay?"

Sans and Papyrus looked at Frisk with confusion.

"WHAT?" Papyrus said. "WHAT DO YOU MEAN...?"

"I mean... I know nobody can see him and just... conclude he's an imaginary friend, but... he's not, to be honest. He's... he's someone quite important."

The skeletons still looked very lost at Frisk's attempts to tell them that Gaster was alive.

"Oh god, I'm really-" Frisk groaned quietly. "He's real and alive!"

"UM... FRISK, WE DO KNOW THAT, BUT..."

"No, y-you don't understand... He's real... for _real_."

"FRISK, WE DO KNOW HE'S REAL! ARE YOU FEELING BAD BECAUSE... NOBODY BELIEVES IN YOU? BECAUSE I DO! I ALWAYS DID!"

Papyrus seriously thought that Frisk simply felt bad for having an imaginary friend and he was trying to make them feel better about it. That was kind of cute, to be honest, but Frisk was sick of people not taking them seriously. Well, they were having a bad time to just reveal Gaster's existence... they were afraid of their reactions.

"It's not that, Papyrus..." Frisk said. "Gaster, h-he... he's a real person, a-and..."

"FRISK-"

"H-He's your FATHER, Papyrus!"

Suddenly, the looks on Sans's and Papyrus's faces changed drastically. Papyrus gasped, shocked and confused, while Sans looked... hurt, too?

"W-WHAT?" Papyrus said.

"I-I mean..." Frisk contained themself, clearing their throat. "He's... your father. He's alive."

"H-HOW... HOW DO YOU..." Papyrus couldn't even say something right.

"I know it seems impossible, but... Gaster really is your father. He told me... h-he survived an accident."

"B-BUT... BUT... HOW'S THAT EVEN... POSSIBLE??"

"I don't know either, but believe me, he's alive and-"

"no, it can't be."

Frisk and Papyrus looked at Sans. He... he looked upset rather than shocked.

"it's... it's impossible, kid." Sans said.

"He _is_ alive, I... I spoke to him, and-"

"no, kid, he's- he's **not** alive."

"How do you even know that?" Frisk asked.

* * *

_what do they even know? i know he's not alive because i have proofs. i know **that**._

"i just know." Sans said, rispid. "you... you don't know what you're talking about."

"I do know!" Frisk sounded angry out of nowhere. " _You_ don't know what I'm talking about! I'm talking about your father, he's alive, he's lost in another dimension!"

_Another dimension..._

No, it... it couldn't be. Sans wouldn't believe in it.

**Not again.**

"no!" Sans yelled. "he's dead! it's _impossible_!"

"Why don't you believe in me? You don't even want to tell me why you are so sure about him being dead!"

"i _just_ know."

"Why do you do this? Why do you hide everything from us?"

Sans suddenly stayed quiet after that... he didn't know what to say in response.

"You keep lying and denying things and... w-why do you do that?" Frisk asked. "Why don't you... trust me? Why don't you trust anyone?"

Sans remained silent. He felt personally attacked, but... Frisk was saying the cold truth. He did lie. He did hide things from other. He... he didn't trust anyone. But... he had his reasons. Nobody would understand them.

God, how did Frisk even know about his and Papyrus's _father_? Did someone tell them about him? Were they crazy? They clearly couldn't be right. There was no way Gaster could've survived that accident.

"i've heard _enough_ , kid." Sans said.

"Sans, for god's sake! Why don't you believe me?"

"because i know he's dead! you don't know _anything_!"

Frisk froze. What did that kid even know? They weren't the one who actually proved that it was impossible. Sick of hearing those crazy lies, Sans left the house, stepping fiercely on the ground.

"SANS!" Papyrus called him, but Sans closed the door and simply walked away.

* * *

Frisk had never seen Sans mad like that before. He was so sure about Gaster being dead, it made Frisk wonder what he had done to find that out. In any case, how great; they didn't believe in them. They shouldn't be that surprised, honestly...

Sans would never believe in them, and Papyrus probably didn't believe, either. He didn't say a thing after Sans left the house angrily. He was trying to process what happened.

"Papyrus..." Frisk said, after a while. "Y-You don't... believe in me, do you?"

Papyrus took a long time to respond. He looked at them with an unreadable expression.

"I..." He said, sighing. "I... I AM NOT... SURE, FRISK. IT'S JUST... IT'S JUST... IMPOSSIBLE. HOW... HOW DO YOU EVEN KNOW HE'S-"

"I _have_ talked to him."

Papyrus breathed deeply. He then looked concerned. Was he concerned about _Frisk_?

"OH BOY..." He murmured.

"Papyrus... I..."

"FRISK, LOOK... WE WILL TALK ABOUT THIS LATER, OKAY? I CAN SEE YOU... YOU DON'T FEEL ALRIGHT AT ALL..." He said. "I BETTER GO AFTER SANS. I DON'T WANT HIM TO JUST... RUN AWAY LIKE THAT. I WON'T LET HIM DO IT AGAIN."

Frisk nodded in response. Well, Papyrus didn't seem to _deny_ that Gaster was alive, but... maybe he was too confused to confirm anything.

"I'M SORRY ABOUT SANS, THOUGH." He said, sighing deeply. "YOU CAN SEE THAT HE DOESN'T KNOW HOW TO DEAL WITH... _IT_."

"No, don't... don't apologize."

"WELL THEN... I BETTER LOOK FOR HIM. OH! WAIT A SECOND!! W-WHAT ABOUT YOU...?"

"Huh?"

"I MEAN, WE WERE SUPPOSED TO TAKE CARE OF YOU, BUT NOW SANS IS GONE, AND I WILL GO AFTER HIM, AND..."

"No, I... I will be okay." Frisk faked a smile. "I promise."

"ALRIGHT THEN... I'LL BE RIGHT BACK. HOPEFULLY. CALL ME IF YOU NEED ANYTHING."

Frisk nodded. Papyrus left the house after trying to give them a smile. They groaned loudly.

"Why...?" They whispered.

Frisk stared at the floor, wanting to cry. They weren't able to save Gaster, nobody believed in them and... and they felt regret for... saying all that to Sans. They didn't know anything about his life and the reasons why he didn't tell anything to anyone. While Sans should be honest, they shouldn't have... misjudged him.

What should they do next? There was nothing they could do about Gaster anymore. They didn't want to give up, they didn't want to leave Gaster alone in the Void for the rest of his life, their determination gave them a slight hope... but a major part of Frisk's mind was telling them that they couldn't do anything.

Frisk sighed, heading to the kitchen. There were was a butterstotch-cinnamon pie on the table. Frisk's appetite suddenly changed and they really weren't in the mood of eating that delicious pie. Instead, the child looked at the window. The sky was clear, with several stars and the wide moon iluminating the garden and the tall trees from the forest. Frisk then opened the door. They knew they would be disobeying Toriel, they even promised they would never do that again, but they just needed some fresh air. The weather was a bit cold, with some gentle breezes. Frisk breathed heavily. They lied among the flowers. The sound of the distant crickets was the only noise that could be heard. It was very calm and relaxing...

Frisk then stared at the stars, suddenly recording Gaster talking about them one night. He was so passionate about science, he talked about stars for a long time. Frisk didn't understand much about science, but they were happy about how he was so excited to go on that topic. Frisk smiled sadly, sighing. Seeing Gaster happy had filled them with joy.

 _I wish there was a way to save you..._ Frisk thought.  _There has to be a way, right?_

But there wouldn't be...

Frisk stood up after a while. They had just remembered that Papyrus wished to talk to them about Gaster later... and there was also Toriel. When she got back, she would like to speak to them, too. They honestly didn't want to think about that... they loved their mom and friends, but... they felt like Sans at that moment; they didn't want to talk about what happened. Not at all.

The human looked at the nice house they lived in, iluminated by the moonlight. They walked through the garden for a while, until... they noticed something.

The basement's door, located in the back of the house... it was... slightly opened.

How strange... that door was always locked everytime Frisk went on to check it. The child had always been curious about what was in there. They have never entered the basement before. Someone might have been in there if the door was unlocked...

Frisk's curiosity didn't stop them from going inside. They pushed the door slowly. It was very dark, but they easily found the light switch and turned the lights on. There was a short ladder. They made it to the ground and... they found several things... but the thing that caught their attention was a big desk. There were several drawers. Lying on the desk were some... blueprints? They were apparently related to some sort of strange machine. Then, there was... something right next to it, covered by a white and dusty sheet. Frisk took a look inside... a strange, kind of big machine. There were some colored buttons, a monitor slightly cracked and a few wires coming out of it. It appeared to be broken, but not busted. Frisk didn't understand why there was a machine like _that_ in the basement. Who would keep a broken machine?

After checking the machine, Frisk went back to the desk. They opened one of the drawers. It contained papers and some old office supplies, but, most importantly, there was a dark blue photo album. They opened it and found several photos of Sans with monsters they didn't recognize. He seemed happy.

Suddenly, Frisk had a random thought: did that machine belong to Sans? Toriel wouldn't keep something like that, would she? Papyrus certainly didn't have any interest in science. Wait, Gaster did tell them about Sans being interested in science ever since he was a kid... Curious, Frisk kept on exploring, even though they were poking around Sans's personal objects. He would _kill_ them if he found out...

They continued to turn the pages from the photo album until... uh?

There was a card pulling out of one of the pages which Frisk didn't notice before. The card contained a poorly drawn picture of three smiling people, with the words "don't forget" written on it.

Frisk gasped when they recognized the three smiling people - Gaster, the smiling man in the middle who wore a black overcoat, and Sans and Papyrus, the little ones who wore blue and red clothes, respectively. That card was so... adorable. After finding it, Frisk was sure that Sans and Papyrus would love to see him again. They knew that Gaster would want to go home, too. He just... couldn't forgive himself for what he had done.

Frisk let the card lying on the desk when they glanced at the blueprints. There were some... drawings of the strange machine. By analising it with attention, Frisk noticed some strange symbols written on it.

Frisk knew that font, somehow.

 _Wingdings_.

Frisk remembered, out of nowhere, that Gaster once mentioned about writing in a different font that used several symbols, including hands.

_Wait a second..._

They read something written on the bottom right of one of the blueprints. Unlike the rest of the writing, it was written in an understandable font:

**PROPERTY OF W. D. GASTER**

**Notes for the Chapter:**

> I hope I didn't make any of the characters OOC here, specially Sans... I just felt like he wouldn't believe in anyone who tells him that Gaster is alive. He has his reasons... you will find out soon.


	9. Misunderstood

Sans could teleport to anywhere he wanted, but he was feeling too messed up to do anything. Instead, he walked away from home, not planning to go anywhere, not even Grillby's. He wasn't quite sure how he felt - was he angry? Upset? Sad? Or maybe even all of these? But what Sans was sure about was that he wasn't mad at Frisk at all. He may have been mean to them, but... Frisk wasn't the reason why he was so broken.

His father was.

Sans didn't know how to deal with his death, unlike... everybody else? It felt like only Sans and Papyrus actually remembered he existed while other monsters appeared of not even hearing of him - not even Asgore, Toriel or Alphys. Papyrus, on the other hand, didn't feel as uncomfortable as Sans when he heard Gaster's name. He had moved on... but Sans would never let him go, no matter how hard he tried. While he honestly wanted his father back, he couldn't bare to believe in Frisk. Why didn't he trust them?

Because he knew Gaster was dead.

Because...

... he had tried to bring him back, once.

He knew how stupid it had been... but he had been young and naive... he had been only a teenager, yet he had already gotten involved with science. Sans loved science, like his father did. A few years after Gaster died, Sans had brought his machine home. He had hidden it in his former house's basement, because he didn't want Papyrus to see it, at least not yet. Sans had always had an idea of how lazy he was... but he had been so... _determined_ to bring his father home that he had spent a great amount of time doing a research about portals and alternate timelines. By considering the theory of another dimension called "the Void", Sans had speculated that his father might have been sent there, after analysing the state of his machine after the accident.

But in the end...

The results weren't like he had expected.

If the Void truly existed... Gaster wouldn't have survived. Sans had discovered that the Void would be an empty and lifeless dimension. No one would ever be able to survive in there. Sans had tried so hard to bring him back, he had had hopes of him being alive... Thus, the skeleton had completely given up. 

Then Frisk said that he was alive, and... Sans didn't have that same feeling of hope anymore.

_**You** don't know what I'm talking about! I'm talking about your father, he's alive, he's lost in another dimension!_

Sans shook his head.  _don't fall for it. you **know** he's not alive._

* * *

Even by walking, Sans was faster than him, and Papyrus was the fastest skeleton to ever exist! Maybe he had been wrong about his speed...

Papyrus thought Sans teleported to Grillby's or somewhere else, but then he spotted a hooded figure a few meters away. He was sure that it was Sans; no one would be that short... and no one would be wearing pink slippers.

"SANS!" Papyrus called him, running in his direction.

As he approached, he noticed that Sans walked a little faster, but at least Papyrus reached him. He grabbed him by his shoulders and turned him around to face him.

"DON'T YOU JUST LEAVE THE HOUSE LIKE THAT!" Papyrus said, somehow pissed, but concerned at the same time.

"l-leave me alone." Sans managed to escape, but Papyrus wouldn't let him go.

"I JUST WANT TO TALK TO YOU! PLEASE-"

Sans teleported himself, escaping Papyrus's grip. He groaned loudly.

"SANS, OH MY GOD! STOP RUNNING AWAY FROM ME!" Papyrus yelled.

Turned out that Sans didn't teleport far away. He arrived in the same street, a few meters ahead.

"WHY ARE YOU DOING THIS TO ME?!" Papyrus yelled.

"i don't want to talk, papyrus."

"BUT THAT DOESN'T MEAN YOU CAN JUST... TREAT ME LIKE _GARBAGE_!"

Sans stayed quiet. He stopped in the middle of the way.

"I'M YOUR BROTHER, SANS..." Papyrus said, about to cry. He hasn't been feeling well ever since he and Sans distanced themselves in the past days... "WHY ARE YOU RUNNING AWAY FROM ME?"

Sans didn't answer. Papyrus sighed deeply.

"IT'S ABOUT DAD, ISN'T IT?" He guessed, then mentally facepalmed.  _GOD, OF COURSE HE'S UPSET ABOUT DAD! WHY DID I EVEN ASK...?_ "L-LOOK, SANS, I KNOW IT CAN BE REALLY HARD AND-"

"no! you don't understand! you can't **possibly** understand how i feel!"

Sans finally faced him. Tears of anger and pain fell from his eyes. Papyrus stared at him with shock. He didn't even remember the last time Sans _cried_. He really was feeling pain.

"SANS... I-I CAN'T UNDERSTAND IF... IF YOU DON'T EVEN TELL ME." Papyrus said, heartbroken. He just... wanted to help Sans. Maybe he didn't like his help... "YOU NEVER TELL ME ANYTHING. HOW CAN I UNDERSTAND IF... I-IF YOU DON'T EVEN **TRUST** ME?

Sans's face softened a tiny bit. Papyrus sighed sadly. He wouldn't tell him anything... why was he even there? He should have left Sans alone.

"I JUST WORRY ABOUT YOU, SANS." The tall skeleton said. "I SEE YOU SUFFERING LIKE THIS AND... I JUST WANT TO HELP YOU. B-BUT, SINCE YOU DON'T... WANT MY HELP, THEN... I GUESS I WILL JUST... GO HOME."

Papyrus turned his back to Sans and started walking away. He couldn't help but cry while he stepped on the sidewalk. He'd better just... go home. Sans didn't want him around.

"papyrus, w-wait! stop!"

* * *

Sans didn't want him to go away. Papyrus was so disappointed and heartbroken... he wished he could help his brother, and... all Sans did was to push him away. He was responsible for this.

Papyrus stopped walking, but didn't look at him. Sans breathed heavily, trying to think of something to say... He didn't want to do that to his own brother. He didn't want him to think he was annoying him. He wasn't at all. Sans just... felt misunderstood.

"don't leave me... please, i just..." Sans sobbed. The anger suddenly vanished, and it was replaced by pure guilt.

Papyrus turned his head to his brother, with a sad expression.

"okay, l-look... i know... i know i should have moved on, like you said, but... i can't let him go, papyrus." Sans admitted. "i'm stupid, i know, but everytime i remember him, i... i feel really..." He sighed.

Papyrus looked away, silent. Sans cried even more, after realizing how mean he had been to his brother.

"and... and i know he's... not alive." He said, remembering he had argued with Frisk earlier. "i know that because..."

Sans didn't finish the sentence. He wasn't sure if he should tell Papyrus what he had done just to bring his father back. He felt like he would tell him he was stupid for thinking that... like what other had told him when his research was still in progress.

_no. no more lying. no more hiding... i won't do this to him again._

"i... i tried to bring him back."

Papyrus turned his head to Sans again. He noticed that he looked surprised.

"it's crazy, i know..." Sans chuckled sadly. "but... years ago, some time after dad's... accident, i had hopes that he was alive. after analysing his machine, i... i thought he was still... alive somewhere. maybe... m-maybe in another dimension. then, i... i spent months attempting to fix his machine, studying how it worked and also how portals worked."

Sans looked away, remembering his reaction to the results of his research.

"i heard about a theory of another dimension called the void." Sans continued. "then i speculated that dad might have been sent to that dimension, considering the portal's destination. b-but then..." He sobbed. "i-it didn't work. i wasted my time, because... the void is a lifeless dimension, and... dad would have been... s-shattered."

Sans heard Papyrus's footsteps approaching slowly.

"it's just.. impossible, pap." Sans said. "frisk's imaginary friend... i-it can't be him."

He finally faced Papyrus. His brother was worried and shocked. Of course, he would have never expected a lazybones to do such a crazy thing...

"WHY DIDN'T YOU TELL ME BEFORE, SANS?" Papyrus asked.

"other people said i was wasting my time."

"WHO DID THAT?"

Sans took some time to respond, while he had another memory of his past.

* * *

_"Sans, why are you doing this?"_

_The young skeleton visited the laboratory where his father had worked. He needed some help from other scientists in order to keep his research going. He talked to one of his father's ex-assistants; the one who told him and Papyrus about Gaster's accident. He revealed everything he was doing to bring Gaster back. The scientist, however, didn't seem to be... very fond of Sans's plan._

_"i know he's alive!" Sans said, confident. "i've studied real hard, and i found out that he may be stuck in another dimension!"_

_The adult sighed. "He did not survive, Sans. You... you shouldn't waste your time. Believe me, there is no way he has survived something like that."_

_Sans frowned. He... he just knew Gaster was alive. He did study, that scientist didn't know anything! He wasn't the one doing the research._

_"He passed away, Sans. It... it is impossible."_

_The young Sans didn't say anything else. He felt disappointed, but quickly, his determination arrived._

**_don't worry, dad. i know you're still out there. i'm gonna save you!_** _He thought, smiling lightly._

* * *

"SANS?"

Sans just noticed he has been out of reality for a while. He shook his head and finally answered: "i searched for help in my research and... dad's assistants and some other people who found out told me i was wasting my time and that... he was dead."

Papyrus's face softened into a more concerned one, rather than shocked.

"i... i was so confident that he was alive, but then... i realized these people were right." Sans sighed. "there's no way he can be alive."

Papyrus didn't say anything. Sans stared at the ground, still crying. He felt ashamed. His brother would probably think the same thing that others had thought about Sans doing everything for his father.

"i'm sorry, pap, i... i should've told you before." Sans said, sobbing. "i thought... i thought you'd say the same."

Papyrus's eyes widened a bit. "REALLY?"

"yea... sorry about that. you're my brother, i should've trusted you, and instead... i treated you like garbage... i just... i felt misunderstood. everyone i knew just told me to get over it." Then, Sans murmured under his breath: "god, i was so stupid. i _am_ stupid."

"OH, SANS..."

Papyrus pulled Sans into a tight embrace. Sans sobbed on his brother's shoulders.

"YOU WERE NOT STUPID AT ALL." He said. "I THINK YOU WERE REALLY SMART!"

Sans sniffled. "y-you... you really think so?"

"OF COURSE! I WOULDN'T BE ABLE TO DO SOMETHING LIKE THAT! YOU STUDIED IN DEPTH AND DISCOVERED SEVERAL THINGS ABOUT PORTALS THAT NO SCIENTIST WOULD EVER KNOW, RIGHT?"

"i-i guess..."

"THEN IT'S NOT STUPID! YOU DID SOMETHING NO ONE WOULD EVER DARE TO DO!"

Sans had never realized that... by thinking about it, no one dared to help him, no one agreed with Sans in that topic. He did end up learning more about portals, aside from Gaster's own invention.

"YOU KNOW... YOU SHOULDN'T BE AFRAID OF WHAT I WOULD THINK." Papyrus said. "I'M YOUR BROTHER, I WOULDN'T SAY SOMETHING LIKE THAT!"

"i know... sorry, pap."

"IT'S ALRIGHT... I UNDERSTAND HOW YOU FEEL. I JUST... WANT TO LET YOU KNOW THAT I WILL ALWAYS BE HERE FOR YOU. YOU CAN TRUST ME WITH ANYTHING."

Sans sighed, tightening his arms around Papyrus. His brother was so cool, so nice and... he was the greatest brother in the whole world. Sans smiled sadly by thinking about it.

* * *

Papyrus was quite surprised that his lazy brother had done something like that, but it made sense. Sans had never let Papyrus enter their former house's basement. It also explained why Sans was so sure that Gaster was dead, and why he easily got mad at Frisk saying otherwise. However, what Sans did to the human wasn't right. Frisk was just a kid who didn't have the same knowledge of science like Sans did.

Papyrus felt bad for his brother. It must have been hard for him to open up... But he was still proud of him.

"sorry for being mean to you and the kid..."

Papyrus faced his brother.

"IT'S FINE, I'M NOT MAD. ABOUT THEM, HOWEVER... I'M NOT THE ONE YOU SHOULD APOLOGIZE TO."

Sans sighed. "yeah, i know, i... i was too hard on them."

"DON'T WORRY! WE WILL TALK ABOUT IT WITHOUT STRESS AND WE WILL FIND OUT WHAT'S UP WITH FRISK AND THEIR IMAGINARY FRIEND." Papyrus said.

Sans nodded. "yeah... y-you're right."

Sans looked away for a moment. Papyrus stared at him. His face was still wet, but he didn't look so hurt anymore. Suddenly... Sans smiled sadly at him.

"thanks, papyrus." He said, hugging him again. "you're the coolest bro in the world."

Papyrus smiled, patting his back. "YOU ARE WELCOME, SANS. AND _YOU_ ARE THE BEST!"

Sans chuckled. "i guess you can say i'm... **sans** ational?"

Papyrus tried to be annoyed, but... not this time. Instead, he laughed softly.

"OF COURSE." He said.

The two let go of each other. Sans seemed a lot better. Papyrus smiled, glad that he was able to help him.

"COME ON, BROTHER." Papyrus said. "LET'S GO HOME."

Sans nodded, sniffling, but still giving him a smile. After that, the skeleton brothers made their way home. Luckily, the house wasn't too far away. Papyrus couldn't wait to arrive home. He just wanted to talk to Frisk about their imaginary friend. Then, after solving everything, they could eat the food that Toriel had left, and they watch some cartoons like they always did! Papyrus was certain that everything would work out.

When they finally arrived, he noticed that Sans looked concerned and regretful. Papyrus gave him a supportive smile, patting his back. Sans returned the smile. The tall skeleton soon remembered that he hadn't locked the door before running after Sans, since he expected to be back home soon. But... the street wasn't dangerous, was it? And maybe Frisk remembered to lock the door. They were a smart child.

However... the door was unlocked. Papyrus found it a bit odd. Frisk would have remembered to lock it, wouldn't they? But the lights of the living room were turned on.

"FRISK, WE'RE BACK!" Papyrus said, happily.

There was no response... Papyrus went to the kitchen, wondering if Frisk was eating anything. Unfortunately, he was wrong; the kitchen was empty, and the butterstotch-cinnamon pie hadn't even been touched.

"FRISK?" Papyrus called them again, walking back to the living room. "HUH, MAYBE THEY'RE UPSTAIRS?"

"let's check."

Sans and Papyrus went upstairs. The tall skeleton suddenly had the awful need of using the bathroom...

"WOOPSIE! I NEED TO GO TO THE BATHROOM! FIND FRISK FOR ME!" Papyrus said, running to the bathroom.

* * *

With his brother in the bathroom, Sans looked at the door of Frisk's bedroom. It was closed. Hesitatingly, he knocked on the door.

"frisk?" He called. "c-can i come in...?"

There was no response. Sans attempted to open the door. It was unlocked.

"are you in there?" He asked.

The lights were turned off. Sans flipped the light switch. The room was empty. There were tons of papers and crayons on Frisk's desk. Sans approached it, curious. Have they been drawing? He didn't want to snoop on their things, but he wondered what have they been up to. Well... turned out that all the papers were blank. Except maybe... for a piece of a drawing covered by the blank papers.

Sans pushed the blank papers away and found a drawing.

...

He gasped loudly.

The drawing was a picture of Frisk, and...

And...

...

 _Him_.

The man next to Frisk looked like Gaster, his father. Even though the work was a bit poorly drawn, the stranger's physical appearence was almost identical to Gaster. He was tall, wore black clothes, had white skin, white pupils on his black eye sockets, he was bald and had no ears. The only thing that Sans didn't recognize was the two scars on his face. Aside from that, Frisk had written two names: their own name, and... Gaster's _full_ name - W. D. Gaster. Under the two figures, Sans read "Best Friends Forever!".

"n-no... it... i-it can't... be..." Sans whispered, astonished.

It was impossible, but... how would Frisk be able to draw Gaster so... **accurately**? How did they even know him... if he was... **dead**?

That meant...

 _oh my god._ Sans thought.  _oh my god, he can't be alive, oh my GOD, I'M FREAKING OUT!_

Sans couldn't breathe well. How was that... happening? How did Frisk even... know him? How... How the hell was he even alive?!

"frisk?" Sans called the child loudly, demanding for explanation. He _really_ wanted to hear something from Frisk about that drawing. Unfortunately, he didn't receive their answer.

"f-frisk, where are you?" Sans called them again, rushing to his and Papyrus' bedroom, still holding Frisk's drawing. It was also empty.

"are you hiding somewhere, frisk?" He then entered Toriel's bedroom, which, again, was empty.

"okay, frisk, that's not funny." Sans said, pissed and... almost freaking out.

 _they wouldn't go missing like that, would they?_ Sans thought, nervous.  _oh my god, where is that kid?!_

Sans rushed downstairs. Papyrus had just left the bathroom and followed his brother.

"t-they're not upstairs, bro." Sans said. "i looked everywhere, it's all empty."

"OH NO!! WHERE ARE THEY?!"

"i-i don't know! b-but... pap, i... i f-found _this_..."

He showed Papyrus the drawing of Frisk and Gaster. Papyrus gasped, staring at the drawing with disbelief.

"W-WHAT-?! IS THAT... I-IS THAT..."

"i-i know, right?! god, i mean... w-what if they... t-they were... **r-right**?!"

"BUT HOW'S THAT... UGH, WHERE HAVE THEY G-GONE TO?!"

Sans and Papyrus stared at each other for a while, tense. The two then screamed and freaked out, running all over the house in order to find Frisk.

"FRISK!" Papyrus screamed. "WHERE ARE YOU?! ARE YOU PLAYING HIDE AND SEEK?!!"

"frisk! frisk, i-is this some kind of joke?! o-or are you mad at me? look, i'm sorry! i..."

He hated to make promises, but he still said: "i promise i'm not here to fight again. i... i-i just want to talk to you!"

Not even that received an answer, and Sans was being honest. He almost lost his breath, thinking about the worst things that could have happened to Frisk that explained their absence in the house.

"oh my god, frisk, where the hell are you?!" Sans screamed. "c-cut that out, kid! y-you're freaking me out!"

"FRISK!!!"

Papyrus ran to the kitchen, opening all the kitchen cabinets and the fridge, calling for Frisk. Meanwhile, Sans, with his magic, lifted every furniture - the couch, the beds and even the wardrobes - to see if Frisk was hiding under them, but they weren't. Papyrus then rushed to the bathroom, and looked inside the toilet.

"FRISK! ARE YOU IN THERE?!" He screamed. No answer...

The two ended up gathering in the living room again. They were deseperate. What could have happened?!

"o-oh my god, this is all my fault..." Sans mumbled, trying to breathe, while sweating. "they're gone, something bad could have happened to them, and it's all because i was a fucking idiot-"

"SANS!" Papyrus interrupted, grabbing Sans by his shoulders. "THAT'S NOT YOUR FAULT! I WAS THE ONE WHO LEFT THE DOOR UNLOCKED IN THE FIRST PLACE AND-"

"o-of course it is! i'm so stupid, they ran away and they will probably never c-come back, and-!"

"WAIT! WHAT IF WE CALL THEM?"

"oh, right! hurry!"

Papyrus quickly picked his cell phone and typed Frisk's phone number. Unfortunately, their cell phone was in the house; they ran upstairs and heard the ringtone coming from their bedroom. The cell phone was on the bedside table.

"AGH!!! THEY FORGOT IT HERE!" Papyrus screamed, almost throwing his cell phone in the ground.

Sans glanced at the bedroom's window. He suddenly had a thought... what if Frisk was outside, watching the stars shine in the darkness of the night? Although they wouldn't do that since Toriel didn't allow them to go outside at night, but Sans really hoped they were still home.

"what if they're outside?" Sans asked, pointing at the window with his free hand, while the other still held Frisk's drawing. "like, in the garden?"

"THEY WOULDN'T DO THAT!"

"bro, come on! they have to be somewhere! besides, they would probably try to... cool down outside."

Papyrus looked at his brother with doubt, but quickly the two ran to the kitchen and opened the door to the back of the house. The skeletons ran around the garden, looking to every single direction and screaming for Frisk.

But nobody came.

"oh my god, frisk!" Sans yelled. "i-i'm sorry! please, come out from wherever you are!"

Sans tried his best to remain calm, but he was so desesperate that he was about to cry again. Papyrus kept on calling Frisk, and he was also freaking out, but... Sans was really scared. The kid could've gone anywhere. What if something terrible had happened?

"k-kid, i swear, i-i... i will never forgive myself if something happened to you..." Sans whispered, almost letting the tears fall from his eyes.

"OH, SANS! WHAT SHOULD WE DO NOW?!" Papyrus asked. "SHOULD WE CALL TORIEL? SHOULD WE CALL THE POLICE?!"

Sans managed to calm down. He wouldn't be helpful if he freaked out. Crying wouldn't bring Frisk back.

 _stay cool, everything will be fine._ He told himself, even though he felt his whole body racing.

He looked around. He saw the dark forest. Sans knew Frisk would never wander around the forest at night. His gaze turned back to the house. There was nowhere else to look, except... for the _basement_. Sans's eyes widened, recording that he hadn't even locked the basement's door after he entered it to see his father's machine and other personal stuff. What if... what if they were there? He could see the door slightly opened, and there was a weak light coming from inside.

"pap, come on!" Sans called his brother, running to the basement's door. "they might be in the basement!"

"WAIT FOR ME!!"

Sans and Papyrus entered the basement. The two, however, stopped in the middle of the short ladder. Nobody was there. The lights were on, though... They must... they must have been there.

"frisk?" Sans called them.

Nobody answered, once again...

Sans and Papyrus walked carefully, looking around the small and disorganized basement. Frisk was nowhere to be seen. Sans then realized that... something was off with the basement. Aside from Frisk, something was missing. Something very important-

Sans stepped on a white, dusty sheet. It was the one that covered Gaster's portal machine. The skeleton just then noticed...

... where was the machine?

Confused, Sans then rushed to the desk. The blueprints... they weren't there, either.

"w-what?" Sans said. "where... where are they...?"

"HUH?"

Sans looked at Papyrus, very confused.

"dad's machine... and the blueprints... t-they are _gone_..." Sans said.

The skeleton unfolded Frisk's drawing and looked at it. He... had a bad feeling. He felt like... the machine and the blueprints' disappearence had something to do with... _Frisk_.

"oh no."


	10. Help

They were being insane, but they were totally willing to do it.

But, aside from that, they still had spent a while figuring out how to take the machine off the basement. Gaster's invention was too heavy to be carried by their own hands. In the middle of the junk in the basement, however, Frisk had found a red garden cart (which seemed to have never been used before) big enough for the portal machine. But the _real_ issue was the stairs. Thankfully, Frisk had a trick - a magic trick. Since humans and monsters studied together in the same school, they could learn how to use magic. Frisk was a beginner, but their magic had been good enough to lift Gaster's machine and the garden cart while going upstairs.

The human child made their way to Alphys's house. She was the only one who could help, as she had a laboratory in her house, even though she didn't spend the whole day doing experiments. Besides, she was a great scientist; maybe she could upgrade the machine and reactivate it. Frisk couldn't help feeling a bit insecure, though. They didn't know if Alphys would believe in them.

In any case, Alphys's house was a bit far away from their house, but, with the help of Frisk's magic powers, they were able to run faster, even if they were carrying a garden cart containing a big portal machine. They started feeling tired after a while, but they refused to stop. Thinking that everything would work and that Gaster might be saved from the eternal darkness filled Frisk with _determination_.

* * *

"O-Oh, hey Frisk! W-What are you doing here?"

Alphys didn't want to sound rude, but Frisk has just arrived at her house without even warning. She was ready for the date she had planned with Undyne. The two of them were going to see an anime movie, but Frisk just showed up. They looked exhausted... It seemed like they had run all the way from their house to hers, it even shocked her. Behind them was a red garden cart, with... wait, was that a _machine_?

"W-What is that?" Alphys asked, utterly confused.

"I-It's a portal machine. Look, I don't have much time to explain, but... y-you need to fix it for me, okay?"

"Hold on, I-I can't just fix a machine without k-knowing the reason! I mean... why should I... fix it? Who built it?"

"It was built by a scientist... the Royal Scientist before you."

Alphys looked at Frisk with confusion, but then she immediately froze when she had a memory of a man working as a scientist for the King decades ago.

"W-What...?" Alphys said.

"I think y-you've heard of him before? His name is W. D. Gaster."

 **W. D. Gaster**.

Alphys had admired that man so much as a child. She didn't know he had died when Asgore revealed to her after hiring her as the newest Royal Scientist. According to the former King of Monsters, Gaster had suffered a grave accident and had been asborbed by his own creation, resulting in his death.

Why was Frisk with his invention? Who had kept it for such a long time? Alphys could see that it was broken and defective, by noticing the wires coming out from it and the crack in the monitor.

"H-How... How did you get it?" Alphys asked.

"It was in the basement of my house. Sans apparently kept it."

"Why would Sans keep it...?"

"Didn't you know that... he's W. D. Gaster's son...?"

Alphys gasped. Was it true? She hadn't heard much about W. D. Gaster's personal life except that he had been married and had had two children. Were Sans and Papyrus really... related to him? Well, it made sense, considering that Sans's and Papyrus's names were based on fonts, just like the scientist's. It was strange, though, that none of the skeletons had ever mentioned him before.

"W-Wait, why... why do you want m-me to fix it?" Alphys asked.

"Well, i-it turns out that Gaster is alive. He survived the accident with his experiment."

" _S-Survived_?! But how?"

"He's stuck in another dimension called the Void. I know this because... I have spoken to him, we started being friends, but... long story short, I-I... I need to save him."

Alphys remained silent. That was too much for her. First of all, the scientist W. D. Gaster, according to Frisk, had survived the accident, when it clearly was impossible. Secondly, the Void wasn't even a... _concrete_ thing. That dimension had never been proved to be real, it was only part of several theories made by the scientists, such as W. D. Gaster himself. None of the scientists had the courage of studying the Void in depth after what had happened to the Royal Scientist. Portals were too risky, considering how grave the accident had been. It had damaged the Underground's laboratory so badly that it had been reformed.

Alphys would always help her friends, but... should she... try to fix that machine? Like, what if the same tragedy happened again? What if someone... _died_?

"F-Frisk, I... I c-can't do this." Alphys said. "I-I don't even know how he is a-alive in another dimension that no one is sure that it even exists..."

"Please... Gaster _is_ alive and he's trapped in that horrible, dark and empty place. He's my f-friend, I can't let him suffer like that anymore."

Alphys gasped when she noticed how sad Frisk sounded. They seemed like they were about to cry. They... they were being serious. Alphys knew they weren't lying, but she had a bad feeling that everything would go wrong if she attempted to fix the machine.

"B-But it's too dangerous!" Alphys said in her defense. "What if the same thing happens? I-I don't want to cause any more disasters!"

Frisk looked down, quiet. Alphys would say something else, but she has just noticed that the human was holding some blueprints.

"B-But... you can upgrade the machine, can't you?" Frisk said, facing Alphys with a sad, but somehow hopeful face. "I mean, you could lower the risks with some new additions, right? L-Like what you did with my cell phone. It... it was really helpful to me. Besides, I think you are a great scientist, I believe you can reactivate it."

Alphys couldn't help but blush. Frisk was being honest; they really did believe in Alphys. Even though her self-image had improved a lot, she still had some insecurity over her own experiments. She didn't see them, or herself, as brilliant. But Frisk did.

"Please, Alphys..." Frisk begged. "I don't want him stuck in the Void for the rest of his life."

Alphys sighed deeply. _I'm going to do something stupid again..._

Frisk trusted her. And Alphys had to say the same for the human. Frisk wouldn't lie about a serious topic, and they were almost crying over W. D. Gaster's supposed imprisionment in the Void. She couldn't say no to them.

"C-Could you hand me these blueprints?" Alphys asked.

Frisk nodded, looking a bit shocked. They offered her the blueprints. She analysed it for a while, specially the drawings of the machine. Although most of the writing was in Wingdings, she was able to translate it.

"I... I-I'll do the best I can." Alphys assured them.

* * *

"HELLO, LADY TORIEL? I-IT'S ME, THE GREAT... PAPYRUS... O-OKAY, I... I-I WANTED TO LET YOU KNOW THAT... F-FRISK IS GONE, AND... I-IF WE ARE NOT HERE WHEN YOU ARRIVE, THEN SANS AND I WILL BE LOOKING FOR THEM, ALRIGHT? WE WILL CALL YOU IF WE FIND THEM OR... O-OR IF WE NEED ANY HELP! P-PLEASE, CALL ME AS SOON AS YOU CAN! G-GOODBYE!"

Toriel didn't answer Papyrus's ten calls. The parent-teacher conference probably didn't end yet, and she might have been too busy to answer her phone. Papyrus ended up just sending her a voice mail. Meanwhile, Sans stared at Frisk's drawing while walking in circles. He had a _terrible_ feeling in his gut. Why... why would Frisk steal Gaster's machine and blueprints? Sans really didn't have a nice thought about it.

_t-tell me they... t-they didn't try to... reactivate it..._

While it was impossible for the machine to be fixed after that accident, Sans still wondered: what if it could? That would be terrible. After giving up on the research that would bring his father back, the other scientists had spoken to him and warned him that portals were very dangerous, which was why Gaster's experiment had gone wrong.

If it was fixed... then it could lead to a tragedy.

Frisk could...

_nonononononononononono- p-please, don't... d-don't do this to me, kid, don't you even **dare**._

Sans panicked as he thought about it. He started sweating even more, his body was at full speed. The feeling in his gut worsened and he lost his breath. He felt like he would die out of fear if something had happened to Frisk. His vision suddenly darkened a little.

_god, n-no! this- this can't be happening **again**!_

* * *

"SANS? SANS!!"

His brother fell on his knees. His left eye was blue and a bright blue flame came out of it. He was panting and sweating, and shaking, and almost crying. Papyrus had never seen Sans in that state before. He ran to him, standing in front of him.

"SANS!!" Papyrus yelled, shaking his brother a little to bring him back to reality.

Sans didn't even notice him. Papyrus put his hands on his face, looking deep inside his eyes.

"C-CAN YOU HEAR ME?!" Papyrus asked. "COME ON, S-SAY SOMETHING! SANS!!!"

Sans gasped and looked scared. Papyrus gazed at him with concern. He looked so terrified. Was... was it because of Frisk? While Papyrus was deeply worried about the child, Sans was  _freaking out_.

"S-SANS, DON'T BE SCARED... IT'S OKAY, EVERYTHING WILL BE JUST FINE." Papyrus assured him, even though he wasn't sure if Frisk was okay at all. "YOU WILL SEE, F-FRISK IS ALRIGHT AND-"

"n-nothing is fine! frisk is gone, and it's all my fault!"

"SANS, DON'T SAY THAT! C-CALM DOWN!"

Papyrus hugged him tightly . Sans was attempting to breathe right, while sobbing uncontrollaby. He sniffled and said:

"g-god, what if... w-what if something bad happened to them, pap? i-i mean... what if they're trying to... r-reactivate dad's machine?"

Papyrus's eyes widened. It made sense. Well, why on earth would Frisk steal a machine and its blueprints? To fix it, of course! But... how would they fix it? Papyrus knew how smart Frisk was, but he was sure that they wouldn't be able to fix a portal machine. Then... they would probably search for help, wouldn't they?

But who would help them? Well, someone who clearly would be interested in science experiments. A scientist, perhaps.

Papyrus gasped.

"OH GOD!!! WHY DIDN'T I THINK OF THIS?!" He yelled, mentally facepalming himself. It made so much sense, why was he so stupid?

Sans faced Papyrus again, still looking terrified, but confused after what his brother said.

"w-what?" Sans said.

"THEY MIGHT HAVE RUN AWAY TO GET HELP TO FIX THE MACHINE!"

"b-but- pap, who would-?"

Sans immediately froze when he realized and his eyes widened. The two brothers said, in unisone:

" _ALPHYS_!"


	11. Breaking the Law

"How interesting... the machine isn't as damaged as I expected..."

After picking her tools in her laboratory, Alphys opened the machine. Its inside was dusty, but, even after the destruction it had suffered (and caused), it wasn't entirely broken. It seemed like someone had fixed a great part of it already.

"I-I might update the operational system and replace the buttons..." Alphys mumbled to herself, but kind of speaking to Frisk, too. "W-Well, I'll do what I can."

Suddenly, she remembered that Undyne would be coming at any minute. Alphys had already promised she would help Frisk, so she quickly picked her phone from her pocket and texted Undyne a message.

"i gotta do something so i might take a little longer. i'll call you when i'm ready"

Undyne answered right away. "what do you have to do?"

"um i'll explain later, i have 2 go now"

* * *

The child approached the work table. Alphys was already replacing the dusty wires and she quickly found a brand new monitor in order to replace the other cracked one. How was she so fast? Alphys sure was a brilliant scientist; no one would work as fast as her.

Frisk looked around Alphys's laboratory. It wasn't as large as the one she had worked in the Underground, but it was way cooler. Its design was very neat and appealing, unlike the simple one of her former lab. The child sighed deeply as they distanced from Alphys to explore the place. They wondered what would Gaster be up to at that moment. He would most likely be fluctuating in the Void, feeling guilty, lonely and hopeless. Frisk could feel their heart breaking by just thinking about their dear friend suffering like that. Gaster didn't deserve that at all, and it saddened them that he thought he did.

They also remembered of Sans and Papyrus. How would they react if they found out that Frisk was gone? Papyrus would certainly freak out, but... Frisk wasn't sure if Sans would even bother. Not after the things they had said to him. Well, maybe he _would_ care, but not about Frisk being gone. They had stolen Gaster's machine from Sans's personal junk. He would only care about his father's invention, honestly. Frisk didn't even know if they were home already. Probably not; Sans could've teleported to anywhere he wanted and Papyrus would search for him in the entire city. Oh, and what about **Toriel**? Parent-teacher conferences usually lasted a long time. She probably didn't even know what was going on. If Toriel arrived home, she would freak out, considering that she worried so much about Frisk since she had lost two children before and-

Frisk shook their head. While their family was the most important thing in their life, Gaster needed them more than anyone. The human didn't want to worry about their own problems, they had to be focused in order to save the scientist.

 _Stop thinking about your problems._ They thought.  _Gaster needs you and Alphys now. Besides..._ They snorted sadly.  _It's not like anyone is looking for you right now._

* * *

"faster, papyrus!"

"WE'RE ALREADY FAST!"

Sans and Papyrus had spent a while trying to figure out how to get to Alphys's house as soon as possible. Sans wouldn't be able to teleport the both of them, since it required a great amount of magic. While Sans had insisted he would be just fine, Papyrus convinced him that they should drive all over the way to Alphys's. In the streets, Papyrus was driving fast, but he was afraid of exceeding the maximum speed limit. He would never break the law, even though Frisk was in great danger. He still followed the transit laws, like, for example, stopping at the red light. Sans was very startled and impatient, unlike Papyrus, who tried to remain calm.

"why are we stopped?!" Sans asked.

"THE LIGHT IS RED!"

"there are NO red lights when our friend is in **danger**!"

It was very unusual of Sans screaming at Papyrus when the opposite usually happened. The tall skeleton groaned loudly after Sans yelled at him.

"SANS, STOP THAT! WE MIGHT GET IN TROUBLE!" Papyrus said.

"but papyrus, frisk can _die_ if we don't get there right away!"

Sans and Papyrus continued arguing until they encountered a frightful and awful traffic line head; a wide, lenghty line of vehicles. The two, astonished, stopped their fight and the car.

"NO!!! WE WILL NEVER MAKE IT IN TIME!!"

He glanced at his brother. Sans's left eye turned blue, staring at the traffic line furiously.

" ** _yes, we will_**." Sans said, his voice deeper and darker than usual. Papyrus had a bad feeling under his spine.

With his magic, Sans lifted all the vehicles in front of them, emptying the avenue. He took control of the car, driving without even touching the steering wheel. Papyrus screamed out of fear while Sans drove the car aggressively, not caring at all about the trash cans, other cars that entered the avenue, not even the pedestrians. His brother was usually calm and would rarely do things furiously. When he did the opposite, it was quite scary, but it was only when someone he loved and cared about was in danger, like what he had done with other kids who had bullied Papyrus when he was just a little kid. He gave them a _bad time_.

God, it was so scary of Sans doing that. He could get them both in trouble!

"SANS, STOP!!!" Papyrus screamed, but Sans ignored him.

Papyrus stepped fiercely on the brake, fighting against Sans's magic. It made the car skid a few meters ahead until it stopped. 

"ARE YOU CRAZY?!" He screamed at Sans, who finally stopped with that madness. "YOU COULD HAVE GOTTEN SOMEONE HURT!!!"

"i don't care! frisk is going to do something stupid if we-"

"THERE'S NO NEED TO BREAK THE LAW!"

"i don't care about the **fucking** law!"

"BEING ARRESTED WILL ONLY MAKE THINGS WORSE! WE WILL BE TAKEN TO THE POLICE STATION AND WE WON'T BE ABLE TO LEAVE UNTIL TORIEL FREES US, WHICH CLEARLY WON'T HAPPEN ANY SOON BECAUSE SHE'S STILL AT SCHOOL!"

Saying that made Sans feel less stressed, yet his eye was still blue. Papyrus knew how terrified and concerned Sans felt at the moment, but there really was no need of getting in trouble!

"LET'S DO THIS IN THE RIGHT WAY, WITHOUT HURTING THE LAW OR PEOPLE!" Papyrus said. "I WILL DRIVE A LITTLE FASTER THIS TIME, BUT DON'T YOU _DARE_ DRIVING THAT WAY AGAIN!"

Sans took a while to respond, but soon his eye turned back to its original color and his expression softened after taking a while to think about what he had just done. He sighed, nodding.

"alright, j-just- just don't waste time, o-okay?" Sans said. "i'm sorry, i-i-"

"I KNOW YOU'RE SCARED, SANS." Papyrus put his hand on Sans's left shoulder. "I AM TOO, BUT LET'S NOT DO SOMETHING STUPID TOO, SHALL WE? FRISK NEEDS US AND WE CAN'T JUST GO AROUND CAUSING TROUBLE!"

Sans sniffled. "o-okay, okay, i'll make sure t-that doesn't happen again."

Papyrus smiled at him sadly, patting his shoulder. He glanced at people who were around. He could hear angry screams from the distance... and he recognized a siren.

It was a _police_ siren.

"AHHHHH!!! NOT THE POLICE!!!!!" Papyrus screamed.

"papyrus, wait-!"

Papyrus stepped on the accelerator, driving as fast as he could in order to prevent prison.

"PLEASE, DON'T ARREST US!!!" Papyrus screamed, looking at the police car chasing them. "I'M TOO YOUNG AND HANDSOME TO GO TO JAIL!!!"

* * *

_This is getting a bit longer than I thought it would... but I'm almost done._

The portal machine, due to the year it had been built, had to be upgraded in many aspects. Alphys, fortunately, was able to rebuild W. D. Gaster's experiment. Frisk watched her doing her job with interest and anxiety. They couldn't wait for it to be done. Alphys looked at the Mettaton clock standing in the wall, seeing that it was time planned for her date. She sighed, wondering if Undyne would feel impatient towards Alphys's incompetence at getting ready. While Undyne was great, she wasn't the best at waiting for a certain period of time...

Thankfully, the machine was almost done. It was all clean, as Alphys removed the dust from the outside and the inside. The new buttons were way cooler than the former ones, and their colors were more nitid. The operational system was updated and contained several new items. The monitor was brand-new and more resistent. The wires were replaced, too. Alphys had an amount of junk in her lab, so it made her job easier, specially with Frisk to hand her the objects and tools.

"Alright, just a few more adjustments and it's almost done!" Alphys said, proudly. She didn't imagine that she would be able to rebuilt an experiment made by a brilliant scientist like W. D. Gaster.

She heard Frisk's footsteps approaching. The child gasped, amazed by the new version of the machine.

"It already looks amazing!" Frisk said. Their mood appeared to have improved.

Alphys giggled, blushing a little. "W-Why, thank you! Well, better keep going, huh?"

* * *

Sans groaned, feeling a bit embarrassed. Papyrus told him to not break the law... yet he was doing the exact same thing. Papyrus had never broken the law before, and he was terrified of being arrested.

More police cars chased after them after seeing that Papyrus wouldn't stop the car. Sans attempted to convince him to stop, but Papyrus wouldn't even listen to him.

"STOP THE CAR RIGHT NOW!" A police officer, who sounded to be a man, screamed.

"papyrus, stop!" Sans yelled.

"NO, I CAN'T GO TO JAIL!!!"

Sans groaned again, finally stopping the car with his magic. The police cars stopped too. Papyrus sweated and froze when one of the police officers walked in their car's direction.

"OH, G-GOOD NIGHT, OFFICER! Papyrus said, shaking. "WHAT A G-GREAT DAY TO CRUISE IN THIS BABY HERE, HUH?!"

The officer looked at them, unamused.

"Get off the car." He ordered.

Papyrus remained still, trying not to scream.

"I said to get out of the car!" The officer screamed.

"look, officer, we're sorry for all the trouble we have caused." Sans attempted to calm him down and convince him to free the skeleton brothers. "w-we're in a rush right now, our friend needs us, and we have to get going."

"Oh no, you are not. You are going to follow me to the police station _right now_."

"N-NOT THE POLICE STATION!" Papyrus whined, crying.

"pap, shhh, it will be okay. we are not going anywhere. watch this." Sans whispered, winking at him.

"You two better get out or else-"

"or else **what**?" Sans's voice became deeper. "look, buddy, our friend is in danger, and if we don't get there they are going to die and something tragic may happen."

The officer froze, but he maintained his firm look.

"Sir, I am getting impatient-"

"i am too, and if you do anything to me or my brother, **_you're gonna have a bad time_**."

" _You_ are going to have a bad time if you don't-!"

Sans pulled the man to face him with his magic. His left eye turned blue, and he prepared a bone attack.

"you clearly wouldn't like to see what will happen next if you don't free us." He asked.

The officer's eyes widened in fear. Sans stared at the man for a while, not hesitant to attack him. Papyrus stopped whining and appeared to have calmed down.

"you better walk away and pretend this never happened, and i swear we won't do this again." Sans warned, serious. "leave before i change my mind about letting you go."

The man nodded. Sans released him, throwing his attack away. The bone ended up damaging the street.

"no hard feelings, right?" Sans winked. "have a good night, officer."

He looked at Papyrus, who quickly drove away, leaving the police officer, and probably his colleagues, in shock. The police cars didn't chase them anymore. His brother didn't say anything about Sans threatening a _police officer_ , but he looked scared. Sans felt a bit regretful for scaring Papyrus, but if he hadn't done that, the two of them would go to jail and they wouldn't be able to save Frisk.

Sans sighed deeply. He got himself lost in his own thoughts while Papyrus continued driving the car without going too fast. He seriously hoped that Frisk, or Alphys, wasn't able to reactivate the machine yet. Sans just wanted to get the kid home and have a long talk about Frisk's drawing and their crazy plan of getting Gaster back. Maybe they could find another solution to Gaster's rescue without doing something so dangerous? He also wanted to apologize for not believing in Frisk when they had told him that his father was alive. Sans should've trusted them. He should've trusted his brother and his other friends, too.

He sighed deeply, closing his eyes.

_kid, don't do anything stupid 'till i get there._


	12. Rescue

"I'm done, Frisk!"

Frisk ran very quickly to Alphys after going to the bathroom. They gasped when they saw the newest portal machine. Its old buttons were replaced by new and more colorful ones, including a big, red button. The new monitor was so clean it acted like a mirror, and so was the entire machine, actually. It didn't have all that dust anymore, and its metals were brand-new, not like the corroded ones. The child gave Alphys a tight hug. She chuckled and returned it.

"Thank you so much, Alphys!" Frisk said.

Alphys faced them with a smile, but it faded as soon as she gazed at the machine. Frisk had to admit that they were a bit afraid of a disaster happening all over again, but their determination was stronger than everything else. The scientist returned her gaze to them.

"I-I hope this is g-going to work." Alphys stuttered. "I-I mean, I didn't even... w-well... l-let's do this!"

She hesitantly turned on the machine by pressing the big button. It was connected to a power generator created by Alphys herself, as it required a great amount of energy. It made a very loud noise and the monitor turned on. Several codes popped in the screen. Frisk couldn't understand them at all. Alphys bited her nails anxiously. The entrance of the portal machine was soon iluminated by a bright, white light. It was so bright that Frisk and Alphys were forced to close their eyes and cover their faces with their arms. After the light decreased, the two looked at the machine again. It... it was surprisingly _stable_. Alphys's jaw dropped.

"I-It... I-It worked! Oh my god, I c-can't believe it!" Alphys said, excited. "N-Now, let's see if this little buddy here works!"

She made her way to the monitor, tapping her fingers on the screen. She configured several things and wrote codes by using a keyboard in the screen. Frisk turned their gaze to the portal machine's entrance. They approached it a little, with a determined smile on their face. They were about to see Gaster again and they would bring him home.

They looked at Alphys again, who looked at the monitor with... shock? Frisk walked up to her, seeing a white point in the middle of the black screen. There was some text but Frisk couldn't understand its font. It wasn't one they recognized.

"Oh my god." Alphys said. "T-There... there really is a p-place... across time a-and space, a-and..."

Alphys's eyes widened in disbelief.

"T-There are... signs..." She said, astonished. "S-Signs o-of... of _life_ in that place!"

That place...

Somewhere across time and space...

Could that be...

"... the Void?" Frisk said out loud.

Alphys looked at them with shock.

"O-Oh my..." She mumbled, sweating a little. "T-There really is s-someone in there! God, i-is that... _him_...?"

"Y-Yes! He's the only one trapped in that dimension!"

Frisk looked at the portal's entrance again. It formed a very bright and white tunnel. At the end of it... Frisk could see the darkness. Nothing, but the darkness and the emptiness of... _the Void_.

"I-I can't believe the V-Void... is **real**." Alphys mumbled to herself.

Frisk sighed deeply, rushing to the part of the laboratory which contained a great amount of junk. They searched for something that could help them enter the Void in order to save Gaster. Meanwhile, Alphys kept on mumbling things while shocked at her new discovery. Finally, Frisk found a lengthy (for real!) rope in the middle of that mess. They wondered why would Alphys even keep it, but they didn't complain at all. They ran back to the machine and tied the rope around their waist.

"W-What are you doing?" Alphys asked.

"I'm going in there."

"N-No, Frisk! It's t-too dangerous!"

"I know I can do this!"

"B-But what if you- what if you g-get hurt?" Alphys asked, in a worried tone.

"Don't worry." Frisk gave her a smile. "I promised I would get him out of the Void. That's what I'm going to do. I can do this. After all, the Void didn't shatter him, did it?"

Frisk prepared themself to jump into the tunnel. They offered Alphys the end of the rope. She anxiously grabbed it.

"I'll be back soon. I promise." They said. "I'll give you a signal to pull me back, okay?"

They jumped inside the portal. Alphys tried to stop them, but she was too late.

"Frisk, no!!" She screamed.

The child jumped to the portal, being sucked by the white tunnel. Frisk stared at the darkness of the end of it, while they heard Alphys's distorted voice screaming for them. They were forced to close their eyes due to the brightness of the tunnel.

* * *

They... they couldn't breathe right. They couldn't feel the gravity anymore; were they... fluctuating?

Frisk opened their eyes. They felt some bad chills by just... looking around. There was nothing in that place. Frisk could only see the darkness. They looked down, only to find... nothing. They really were fluctuating, which... made them feel much more lighter. Frisk looked behind. The portal was the only light source in there.

They really were in... _the Void_.

The human attempted to move. They couldn't run or walk. Instead... they swung their arms and legs, noticing they moved a little bit. Frisk began "swimming" in the emptiness of the Void. That dimension was just like how Gaster had described it: a black space, with no stars or... **anything** , actually.

"H-Hello?" Frisk said, looking around.

There was no response. They swam away from the portal, trying to find at least a white spot, since Gaster wore a black overcoat.

"M-Mister Gaster?" They called him. "Are you there?"

* * *

_That is right._

_This is where you belong._

Gaster sighed deeply, resisting the urge of crying. He had broken the heart of a dear friend, but... he had done the right thing. Everyone was unhappy with his presence. He shouldn't have come back at all.

_Home, sweet home._

Gaster couldn't think about that look of a broken heart that Frisk had had on their face when he was about to leave. He heard Frisk's voice echoing in his mind.

**That's not true! You are a great person! You are a great and dedicated father, and... you're my best friend!**

**You're my best friend!**

_**You're my best friend!** _

**_OH, F-FRISK..._** Gaster said, sniffling.  ** _YOU WERE MY BEST FRIEND... THE ONLY ONE I HAD._**

He felt deep regret after remembering all the good times he had with Frisk. The subjects they talked about, the fun they had with Sans and Papyrus, the human television... Frisk... Frisk was one of the best people to ever come to his life. They were just as important as his sons were to him.

 _ **I... I SHOULDN'T HAVE... ABANDONED YOU.**_ Gaster said, sighing again.  ** _Y-YOU... YOU WERE MY ONLY FRIEND... YOU UNDERSTOOD ME, COMFORTED ME, LISTENED TO ME WHEN NOBODY ELSE WOULD. Y-YOU HAVE BEEN THERE FOR ME. AND I... I JUST... LEFT._**

 _But you did the right thing. You have ruined their life._ The distorted voices said.

Gaster didn't answer them. He stared at the darkness of the Void, almost bursting in tears. He felt his heart ache even more by remembering that the world functioned well without him.

 _You have ruined everybody's lives. The whole world was doing well without you._ The voices then laughed creepily.  _You pathetic garbage... You should have given up instead of still holding that miserable hope in your heart. Nobody wants you. Nobody needs you._

Frisk suddenly showed up in front of him. They gave him a sad smile.

 **I can be your friend, Mister Gaster.** The child said, their voice echoing.

**Please, don't go.**

_**FRISK, I-** _

Gaster tried to touch them, but Frisk vanished. The scientist closed his eyes, letting the tears fluctuate.

 ** _I'M SO... I'M SO SORRY._** He said, sobbing.  ** _I-_**

"H... H-Hello?!"

Gaster froze. Was that another hallucination? It could be just... the Void tricking him.

"Mister Gaster?" Frisk called.

 _ **NO, NO, I-I CAN'T TAKE THIS ANYMORE-**_ Gaster mumbled to himself, shaking his head and closing his eyes.

The Void was playing with his mind again. It always did that. Gaster would always have a hallucination of someone he cared about, mostly Sans and Papyrus, and then Frisk, Gaster just wanted it all to stop. Those visions he had could have driven him crazy. His pain and his self hate just worsened by each time the Void tricked him. Why... why couldn't he just... _die_ already? Death would be way better than stay alive and remember all the mistakes he had made.

 ** _S-STOP THIS!_** Gaster spoke... to the Void?  ** _I-I JUST WANT- I JUST WANT TO DIE! I CAN'T TAKE THIS ANY LONGER!_**

 _It really would be better for everyone... But you are not dead. You cannot die._ The distorted voices laughed.  _You will suffer forever, and you deserve this, you idiot!_

"Mister Gaster? C-Can you hear me?" Frisk asked.

Gaster denied Frisk's existence. The distorted voices yelled inside his mind, saying several pessimistic things to him. He couldn't take it anymore. He let out a scream, letting more tears come out from his eyes.

 ** _STOP!_** He yelled.

The voices spoke louder, until... he heard a scream from someone else.

"M-Mister Gaster!"

Gaster opened his eyes. Nothing in front of him... He turned to the other direction, only to find... Frisk.

 **IT'S NOT REAL, IT'S NOT REAL, IT'S NOT REAL-** Gaster thought, after the voices finally became quiet.

The supposed Frisk sniffled, but still smiled.

"G-Gaster..." They whispered.

 ** _THIS- THIS IS NOT REAL-_** Gaster said to himself out loud.  ** _I-IT CAN'T BE REAL-_**

"W-What? I'm right here, mister Gaster!" Frisk answered.

Gaster analysed the child. Their waist was tied by a lengthy rope, which came from... _wait_... He looked behind the child, finding a... was that... a **portal**? It was a white, bright and long tunnel. The scientist's eyes widened. The Void would never be able to do something like that, specially when it was slightly iluminated by the light tunnel.

It wasn't a hallucination.

 ** _F-FRISK, WHAT... W-WHAT ARE YOU... D-DOING IN HERE?_** Gaster asked, astonished.

"I came here to rescue you!"

**_R... RESCUE ME?_ **

How was Frisk able to enter the Void? How did that portal appear? God, did... did Frisk go in that dark place just... to save _him_? That awful, horrible and worthless piece of garbage?

 ** _H-HOW DID YOU GET HERE?_** Gaster asked.

"I-It doesn't matter now! Come on, I'll take you home!"

Frisk swam closer to him. Gaster remained still, too shocked to do anything. The distorted voices returned to his mind.

 _LEAVE FRISK ALONE! LET PEOPLE LIVE THEIR LIVES HAPPILY!_ They yelled at him.

Gaster distanced himself from the child.

 ** _G-GET AWAY FROM ME!_** He yelled, sobbing.

"W-What-?"

**_GO AWAY, FRISK! THIS IS NO PLACE FOR A CHILD!_ **

"This isn't the place for you, either! I won't let you stay trapped in here!"

 _ **GO HOME ALREADY!**_ Gaster screamed louder, feeling his headache getting worse because of the distorted voices yelling mean words at him.

* * *

Gaster sounded so distressed, so broken and hurt... It hurted so much to see him like that. The Void was a _prison_. It had changed him, it had destroyed his positive thoughts, his hope. Frisk attempted to approach him, but he refused to go with them. His body... it started melting again. His face became completely disfigured, it was too painful to watch.

"M-Mister Gaster!" Frisk screamed, terrified.

Frisk swam closer to him again, only to make him almost push them aggressively.

 ** _LEAVE ME ALONE, FRISK!_** Gaster yelled, sounding enraged but upset at the same time.  ** _I DON'T MATTER!_**

Frisk couldn't help but cry, too. Their tears fluctuated among them.

"S-Stop running away from me!" Frisk said. "I just want to help you!"

**_I AM NOT WORTH HELPING! LEAVE NOW BEFORE I MAKE YOU!_ **

Gaster turned his back to Frisk, sobbing loudly and shaking his head. The child's eyes widened in shock. He had been through horrible times. He was being manipulated by the pessimistic forces of the Void. He thought he wasn't worth it. Frisk had to prove him otherwise, because he was a great friend and father.

Firstly, Frisk gave him some space. He wasn't comfortable with anyone approaching him and they understood that. Secondly, they picked a piece of paper from their pocket.

"Mister Gaster?" They called him.

**_JUST LEAVE, FRISK!_ **

Gaster turned his head to them. His face was worse than before. His white pupils disappeared. His black eyes were just like... the void. He gave them an angered face. Frisk unfolded the piece of paper, revealing the adorable card of Sans, Papyrus and Gaster. They immediately showed it to him.

"Don't forget."

* * *

Gaster suddenly... felt himself calm down a little. The scientist stared at the drawing of him and his sons, and reading "don't forget" numerous times.

 ** _H-HOW DID YOU-_** Gaster mumbled.

"It doesn't matter. I just... I just want to tell you something."

Gaster remained silent. Frisk sighed.

"Don't forget that... there are people who deeply care about you. Who love you for who you are." They said. "You are not a horrible person. Everybody makes mistakes, and... nobody is perfect. Besides that, you... you care so much about others, you are willing to do everything for the ones you love. That's why Sans and Papyrus admire you so much. They understand that you work hard just to give them the best. That's why they love you."

Gaster overthought every single word Frisk told him. They... they were right. Sans and Papyrus never stopped loving him, even... even after he distanced himself from them. They would always let him know how much they cared about him, they would always say that their father was amazing.

"That's why... I love you, too." Frisk continued. "You're my best friend, mister Gaster. You... you may not see it, but... Sans, Papyrus, and I..."

Suddenly, Gaster could hear Sans's and Papyrus's voices when Frisk said:

" _We think you're pretty great_."

The scientist looked at the child, not sure what he should do. He... he felt better, but startled at the same time, specially after hearing his sons' voices.

"You can go home now." Frisk said. "You can finally be free, not only from the Void, but from the Underground, too. You can live in the human world, you can cherish your freedom in the surface, watch and study the stars, like you said you have always wanted to do, and... you can be part of a family, too."

Frisk offered their hand to Gaster. Behind them, he... he saw Sans and Papyrus. The two of them smiled at him. Tears formed on his eyes, but this time... they were tears of _joy_. Frisk was absolutely right. He wouldn't be trapped any longer. He wouldn't be under pressure because of his work. He wouldn't be fluctuating in the darkness anymore.

He would be free.

He would be **home**.

Gaster couldn't help but... smile. Frisk was really crazy to create a portal in order to rescue him. However, if that child entered the Void just to save him... how bad could he be?

He felt something inside his heart. He felt... something good. Something _great_ , actually. It... it was...

... Happiness.

... Love.

Love for his dear friend. Love for his sons.

Gaster didn't feel anything negative any longer.

"Come with me." Frisk said with a smile. "Let's go home."

* * *

"Oh god, oh god, oh god-"

Alphys mumbled that the whole time while holding the rope. Frisk had been inside for a while by now. Did something happen? Well, Frisk would give them a signal to be pulled back, right? Alphys trusted them, she... she believed in them, despite feeling deeply concerned about their safety.

 _Calm down, just... relax._ She thought.  _Nothing bad will happen. Frisk will be alright. They give you a signal, you pull them back and then you send them home right away. See? Nothing to worry about-_

"Alphys?"

Alphys froze. That voice... that woman's voice... it was quite familiar.

The scientist looked behind her. Undyne was standing there, looking at her with a confused face. She looked very stunning with that black jacket, those black boots and blue jeans... But Alphys couldn't compliment her girlfriend when her friend was in another dimension.

"U-Undyne! I... I-I was about to g-get ready!" Alphys stuttered nervously. "I... I-I am just... d-doing science things! I'm almost done with this and t-then we will go see that movie, okay??"

Undyne glanced at the machine.

"What... what is that machine?" She asked, then turning her gaze to the lengthy rope. Her face frowned.

"What's with that rope?" Undyne asked.

"Uhhhhhhhhh........."

 _Don't you dare lie to her. You promised you wouldn't lie to anyone any longer._ She thought.

Alphys sighed deeply. "O-Okay, look, U-Undyne..." She cleared her throat. "Don't f-freak out, but, huh... t-this machine here is... i-is a portal machine! A-And... Frisk a-asked me to fix it so they c-could rescue someone i-in another... dimension...? W-Well, there's no need to worry about it, r-right?" Alphys forced a smile.

Undyne's eyes widened in disbelief.

"WHAT?!" She screamed. "You let Frisk enter another DIMENSION?! How- Oh, wait a second. Don't you tell me that Frisk is in the other side of the-"

Alphys looked away, guilty.

"No." Undyne said, not believing it.

"Undyne-!"

"Alphys, WHAT THE HELL?!" Undyne screamed, approaching her furiously. "YOU GET FRISK OUT OF THERE RIGHT THIS INSTANT! THIS IS TOO DANGEROUS FOR A KID!"

"B-But-!"

Suddenly, a loud noise could be heard. That wasn't a good signal. Alphys felt herself being pulled closer to the portal. It... it seemed to... absorb her!

"UNDYNE! HELP!!!" She screamed.

She felt a tight grip around her waist. Undyne stepped away from the machine and grabbed the work table which, thankfully, was stuck to the ground. Alphys could see the screen of the monitor full of error tabs and the red alarm rang loudly. The portal was unstable. Both Undyne and Alphys gasped.

"Nonononononononononono-" Alphys mumbled, shaking her head and then screaming: "FRISK!"

Alphys looked up to Undyne, who was terrified.

"P-Pull the rope!" She ordered. Undyne nodded.

The fish lady let go of Alphys, who quickly grabbed the work table. The two tried their best to pull the rope as fast as they could. Unfortunately, the portal became more and more unstable as the time passed.

"Oh my god, no!" Alphys said to herself, hoping that Frisk was okay.

* * *

Frisk and Gaster looked at the tunnel. It... its form was becoming distorted. They could hear loud and distorted noises coming from it. Gaster gasped. He knew what that meant: the portal was becoming unstable. It... It could _explode_ in any minute!

 ** _T-THE PORTAL IS UNSTABLE! IT MIGHT BE DESTROYED!_** Gaster screamed, scared.

"T-Then we have no time to lose!"

Gaster nodded. He held Frisk's hand. The child, thanks to the low gravity of the Void, was able to pull him closer to them. Frisk pulled the rope, like they were giving some sort of signal. Suddenly, the rope started being pulled violently to the portal.

* * *

"NGAAAAAAAAAAAAAAAAAAAAAHHHHHHHHHH!!!!!!"

Undyne, with all of her strength, pulled the rope aggressively. Luckily, the two of them were able to stand in the ground without holding onto anything. Alphys was right behind her, doing the same. Undyne really didn't know why on earth was Frisk inside another dimension just to rescue someone when Alphys or anyone more recommended to do such a dangerous task could do that, but she wouldn't let Frisk die!

The portal's form was distorting. Its alarm sounds echoed the laboratory. The machine absorbed several light things from the junk in the corner of the lab, such as wires and blueprints. The rope was being absorbed by the portal, and Undyne had to be stronger than ever before.

"DON'T WORRY, KID!" She screamed, unsure if Frisk would hear them. "I'LL GET YOU OUT OF THERE!"

* * *

Light rays were coming from the tunnel. The Void... The Void was... _brightening_. Gaster panicked. If they didn't make it on time, the portal would explode, and... and something terrible would happen to the both of them. In the other accident, the destruction had been so grave that it could have **killed** Gaster. He was very lucky to have survived, but his head had been cracked, which explained the two scars on his face.

 ** _OH GOD, T-THIS IS TOO DANGEROUS!_** Gaster yelled.

"I know!"

**_FRISK, IF WE DON'T MAKE IT... S-SOMETHING TRAGIC CAN HAPPEN TO YOU!_ **

Frisk looked at him with shock, but they frowned and looked at the portal, showing determination in their eyes.

"Everything will be fine!" They screamed. "I promise!"

**_FRISK, YOU CAN DIE IF THE PORTAL EXPLODES!_ **

"Gaster, I- I just want to get you home! A-And I'm doing this, even if... if something happens to me! B-But I promise that everything will be okay!"

A loud noise could be heard. The portal was more and more unstable. The Void was almost entirely white, and it was utterly creepy. Gaster gasped loudly.

 ** _WE ARE NOT GOING TO MAKE IT!_** He screamed.

" _Yes, we are_!"

They were getting closer to the tunnel.

* * *

Light rays were coming out of the portal. Undyne strived so hard to pull the rope that Alphys could see the veins in her muscles. Her face sweated, and she screamed very loudly as the machine was close to destruction. The monitor cracked in a frightful speed and the metal that protected the machine's wires and the computer was _shattering_.

"NO! I WON'T LET YOU DIE IN THERE, FRISK!!!" Undyne screamed.

"Frisk!!"

The two pulled the rope at full force, trying their best to not to be absorbed by the portal. Alphys panicked, already blaming herself for putting Frisk in danger. She believed that they could save W. D. Gaster and return safely. She shouldn't have let them do that.

"Come on!!" Alphys screamed, feeling exhausted.

Undyne and her froze when they saw the portal cracking. More light rays were coming from it. The machine would explode!

"NO!!!" The two screamed in unisone.

Undyne pulled the rope so hard that both of them fell backwards. Then everything turned bright, and a loud explosion noise could be heard.

* * *

"WE'RE GOING TO MAKE IT!!!"

Finally, Sans and Papyrus were almost getting to Alphys's house. Sans's shortcuts, unfortunately, didn't quite work. The traffic was terrible everywhere. Papyrus accelerated a little more, forming a wide smile on his face. Sans was smiling too, and... he had the urge to cry. He was so guilty, so regretful, yet glad that he would be seeing Frisk again. He couldn't wait to see that determined face of theirs and take them home.

"we're almost there-"

The ground shook violently. A loud noise could be heard from a short distance. A very bright, white and wide laser light came out of Alphys's house. Sans's and Papyrus's visions were blocked by its brightness. Papyrus lost control of the car, making it skid. The two screamed, attempting to stop it, but the light prevented them from doing so. Before Sans could at least try to use his magic, the car crashed into a wall. He lost his senses.


	13. Determination

"Mister... skeleton? Can you hear me?"

Sans groaned, opening his eyes. His whole body was aching. His vision was blurry, but it was slowly getting better. He could see two shadows in front of him, but he couldn't recognize them.

"God, that accident was serious." A woman said. "He is very lucky to not have turned into dust."

As his vision was getting better, Sans was able to recognize that the two people weren't humans, but monsters. The skeleton managed to sit, but he had difficulties due to the pain. The two monsters helped him.

"A-Are you alright, sir?" The male monster asked. "Hopefully the magic will cure you in a short period of time."

Sans looked around. His vision was still blurry, but he saw several people around. He heard some screams and gasps, and police sirens. He glanced at something that appeared to be a wall and... he gasped. His brother's car was completely damaged and it was being winched. Sans quickly lost his breath when he realized that Papyrus wasn't around. He attempted to get up, only to make him feel more pain.

"w-where- w-where is my b-brother?!" Sans asked, panicking.

"C-Calm down, mister! Y-Your brother is okay, he... well, the other monsters are still trying to cure him. Please, remain calm, the magic still has to make effect-"

Sans didn't care about his well being. He just wanted to see Papyrus. He ran away, pushing the two monsters and almost tripping. The pain in his stomach worsened, but he didn't stop running.

"papyrus?!" Sans called him.

"S... S-SANS...?"

Sans looked to where the voice possibly came from. He saw his brother standing up with the help of some humans. He ran to his brother, giving him a hug.

"p-papyrus! god, a-are you- are you o-okay?!" Sans asked, worried.

His vision went back to normal. Papyrus's face was bruised and he had a dizzy and confused expression on his face. He looked at Sans with concern, taking a while to return the hug.

"W... WHAT HAPPENED?" Papyrus asked. "I... I DON'T REALLY REMEMBER ANYTHING."

"w-we were going to alphys's when a light came from her house and-"

Sans froze. The... the laser light... It was a terrible sign. Sans recorded of his father's assistants describing the portal's destruction, and they mentioned a wide, bright laser light coming from it. The damage it had caused was catastrophic. The skeleton looked behind his brother and the humans, only to find several police cars, some ordinary people and monsters and... a white smoke which covered Alphys's house.

They were too late.

 _no, no, NO!_ Sans thought, running as fast as he could.

"W-WAIT, SANS!" Papyrus called him, but he ignored him.

He couldn't have arrived late. Frisk couldn't have...

"f-frisk?!" Sans yelled as he approached Alphys's house. The police officers blocked his way.

"You cannot pass this area!" One of them said.

"get out of my way!" Sans screamed, pushing them away.

The police officers grabbed his arms. Sans growled and teleported himself to Alphys's house. He arrived at the living room, making his way to the laboratory.

"frisk!!" Sans screamed as loud as he could.

He found some police officers and firefighters in front of the lab's door. They noticed his presence, attempting to approach him.

"S-Sir, you have to leave, it is dangerous for you to-"

"i don't care!" Sans interrupted them, pushing them. They didn't try to stop him.

The whole laboratory was covered by a white smoke. Sans coughed, not being able to see anything. He was panting, he could feel his left eye flaming. Tears formed on his eyes. He ran around the laboratory.

"frisk! a-are you here!?" Sans screamed.

There was no response. He seriously hoped that Frisk was around, but... deep inside, he had the feeling that the child wasn't in the laboratory. Not... not anymore. Sans continued running until he stepped on something. Something hot, it almost burned his pink slipper. Sans picked that thing up. It... it was a rope. At least a part of it; its end was black. It appeared to have been removed. Sans had a bad feeling about that.

_nononononononononono-_

Right in front of him, Sans could see... something big. He ran in its direction. He gasped loudly.

It was... it was Gaster's machine. The metal that once covered it was removed, some pieces of it were on the ground. All the wires were coming out of it. A cracked monitor was on the ground, too. A power generator had exploded. God, the machine was... was _busted_. Sans felt his heart break in a million of pieces. Frisk couldn't have... they had to be alive, right?!

"f-frisk?!" Sans called them again. He heard footsteps coming from the distance. The firefighters were right behind him, but they didn't say anything, only letting out some gasps. The skeleton looked around, holding the rope tightly.

"p-please, t-tell me you didn't..." Sans sobbed. "n-no... _no_..."

Sans fell on his knees, staring at the burnt rope.

It was too late.

Frisk was gone.

He just... knew it, by looking at the incomplete rope.

"frisk, d-don't do... don't do this to me, i-i can't- i-i can't lose you, too!" Sans screamed.

He kept on calling for Frisk...

... but nobody came.

"no... NO!" Sans screamed, after realizing how dumb it was to call for them. " **FRISK**!"

He... he failed. He failed at saving his dear friend. Frisk just wanted to help his father. They just wanted to save another life, and... and they ended up losing their own. And it was all Sans's fault. If only he had believed in them... He should've believed in them instead of just... being a fucking ignorant.

"i.... i'm so sorry... g-god, i'm a piece of _shit_ -" Sans mumbled, sobbing.

He looked at the machine. He approached it. He growled loudly and hit the machine hard, falling on his knees again. Suddenly, he heard a noise coming from his father's experiment.

Sans's eyes widened. He heard screams coming from the police officers and firefighters. Sans quickly ran away. The machine was making a loud noise and, all of a sudden, it exploded again. The whole laboratory was gone. Sans fell on the ground, making a "oof!" sound. He looked at the former laboratory. The machine... it caught on fire. He heard his brother screaming.

"SANS!!!" Papyrus ran to him, helping him to get up. "OH MY GOODNESS!! ARE YOU HURT?!"

Sans couldn't even think of what he should say. He... he didn't have the heart to tell Papyrus what had happened to Frisk. He still held the burnt rope.

"W-WHAT... WHAT ARE Y-YOU DOING WITH THAT ROPE-?" Papyrus finished the sentence when his eyes met Sans's.

Papyrus's jaw dropped. "NO, IT CAN'T BE..."

Sans nodded his head, sobbing loudly. He wrapped his arms around his brother tightly. Papyrus was too startled to do anything.

"NO... S-SANS, D-DON'T TELL ME THAT... PLEASE..." Papyrus mumbled, sniffling.

Sans didn't let go of him until he heard Undyne and Alphys calling their names. They were injured, too, but they were able to run without almost tripping.

"Sans? Papyrus?" Undyne said. "W-What happened to you?!"

Sans and Papyrus didn't even answer her question. They just continued on crying over the burnt rope. Alphys's eyes widened when she noticed the rope in one of Sans's hands.

"T-The rope... O-Oh... O-Oh no, oh god, no-!" Alphys said.

Undyne closed her eyes, appearing to be regretful.

"No... I-I... I wasn't... strong... _enough_..." She whispered to herself, resisting the urge to cry.

"U-Undyne-"

Undyne pushed Alphys away. She sniffled and walked away, stepping fiercely on the ground. Alphys sighed deeply. The skeletons stared at her.

"I- I'm sorry." She said, running away and crying.

Sans and Papyrus were left alone with the burnt rope for a while, until other people (humans and monsters) approached them.

"We- we need to take you two to the hospital." One of the monsters said. "You are seriously harmed."

The skeletons stared at each other, finally letting go. Sans didn't want to. He didn't want to let anyone else go.

"T-THANK YOU, BUT... WE ARE OKAY." Papyrus lied. "WE WILL GET BETTER SOON!"

"b-but pap-"

"HEY, IF ANYTHING HAPPENS, I CAN STILL USE MAGIC, RIGHT?" Papyrus said.

Sans sighed deeply. They could use magic... but they couldn't heal themselves entirely. They couldn't heal the broken hearts.

"L-LET'S... LET'S JUST... GO HOME, SANS." Papyrus said, sniffling. "THERE'S NOTHING ELSE W-WE CAN DO... FOR _THEM_."

Sans nodded sadly.

"w-what about your car?" He asked.

"I... I WILL TAKE CARE OF THIS LATER." Papyrus sighed. "L-LET'S JUST LEAVE, SANS..."

* * *

He heard... several noises. Police sirens, people screaming and gasping... He... he breathed. He could smell the air. The smell wasn't pleasant at all, though.

Gaster groaned quietly. He felt something almost crushing him. He tried to push it away with his left arm. When he broke free of that heavy thing crushing him, he looked around. He couldn't see anything right. He felt very dizzy, his vision was slightly blurry, only to find a white haze. However, he... he did see some distant shadows. There were several of them. He also recognized the blue and red lights of the police cars in the distance. Gaster was very confused. He felt something odd... something on his right arm. Something small. He looked down, gasping without making a sound. Frisk... Frisk was on his arms. Their face had several bruises, some of them were bleeding. Their blue sweater was bloodstained. Frisk's skin was pale, their eyes were closed. God, they... they were so cold. It seemed like they were... **dead**.

 ** _F-F... F... FRISK?_** Gaster stuttered.

The child didn't answer. They didn't even move. Gaster suddenly recalled that he had tried to protect Frisk from the damage caused by the portal's destruction. Well, he did feel a severe pain on his back, but... he kind of ignored it. Frisk was more important. Gaster had risked his life in order to save the child, yet... no, he couldn't have... failed. They- They couldn't be...!

 ** _F-FRISK?! S... SAY SOMETHING!_** Gaster said, terrified.

He put his hand on Frisk's chest. Their heart... it wasn't beating. They weren't breathing.

 ** _NO, F-FRISK! P-PLEASE!_** Gaster sobbed.

Gaster could feel his body... turn into dust. He felt his head slowly vanishing. No, he... he couldn't die. Not yet. He was able to see Frisk's soul - a red, small heart in their chest. It was cracking slowly. It wasn't too late. Gaster breathed heavily.

 ** _NO... N-NO!_** Gaster said to his body, angrily.  ** _I... I WON'T DIE! N-NOT... NOT YET! I... I CAN'T DO THIS TO FRISK!_**

He felt like his body was breaking into several pieces, like some sort of glass breaking. Gaster stared at Frisk, clenching his right fist while the left hand held on Frisk's sweater tightly.

 ** _I WILL NOT DIE! DON'T WORRY, FRISK, Y-YOU WILL BE ALRIGHT._** Gaster told them, even though they clearly wouldn't listen.  ** _I... I PROMISE YOU WILL BE OKAY. I... I WON'T LET YOU DIE. I WON'T ABANDON YOU. N-NOT... NOT AGAIN._**

He was panting, his eye pupils turned purple. He wouldn't disappear just yet. He wouldn't give up. He wouldn't let Frisk down.

 ** _I WON'T DIE!_** He screamed loudly.

Gaster strived to not turn into dust. It... it worked. But... he felt himself fall apart. He felt his body melting, but... he didn't feel like he would die. Instead, he felt something... something strange inside his heart. Something that wouldn't let him die. It was very odd, yet so strong, so... so... Gaster couldn't really describe it.

He stood up, almost tripping. His body was slowly melting, but he didn't care. He just wanted to get help. He wouldn't let Frisk die. That strange feeling would prevent his death.

He...

He was filled with _determination_.

He growled loudly, fighting against his death while walking. He stepped on several things, mostly the ruins of some kind of laboratory. Gaster felt Frisk's blood on his hands. He looked at them once again. It was painful to watch that poor child in that state. It... it just increased Gaster's determination to save his dear and only best friend.

He worked really hard, but soon, he made it to the street. At least he thought it was a street, considering that there were police cars. He heard loud gasps coming from people. Gaster's vision darkened, getting more and more blurry. He felt his heart... stop beating...

 ** _H.... H-H.... H-HELP..._** That was his last word before everything turned black.


	14. Relief

_WHAT WAS THAT?_

In their way to a bus stop ahead, Papyrus was sure he heard people gasp loudly at something. He looked behind, only to find the crowd still surrounding Alphys's house. What could have happened? Papyrus glanced at Sans, who apparently didn't notice. He stared at the burnt rope with grief and guilt, holding it tightly. Papyrus didn't stop walking until he heard screams.

"Quick! He's turning into dust!" Someone, who sounded to be a man, screamed.

"Oh god, poor child! T-They are BLEEDING!" A woman yelled, desesperate.

Child...

Papyrus had a bad feeling about this. He ran as fast as he could to the crowd, almost tripping due to the pain he felt after the car accident. He heard Sans calling his name, but he didn't stop. Papyrus pushed people without even warning. Finally, he stopped when he saw Frisk on the arms of a human woman. They were pale and a lot of blood was coming out of their belly. Next to them were five monsters surrounding someone laying on the ground. They were probably using magic to heal a stranger who Papyrus couldn't see.

"FRISK!" Papyrus called them, tripping when he ran to the woman and Frisk's direction. He moaned in pain.

"p-papyrus!"

Sans helped him to get up and looked at him with a concerned face.

"are you okay?" Sans asked. "what happened-"

He stopped talking when his gaze focused on Frisk. The woman was screaming for an ambulance. The monsters who healed the stranger looked very tense.

"w-what the-?! FRISK?!" Sans screamed, running to the woman, who tried to distance Frisk from him.

"Stay away!" She said. "They are-"

"YOU stay away! i am their friend!"

He took the child off her arms aggressively. She attempted to get them back, but Sans glared at her with a scary look.

"stay. away." He said, his voice darkening. The woman stepped back in fear while Papyrus approached his brother slowly.

"F.... FRISK..." He mumbled. "OH... GOD..."

"frisk? c-can... can you hear me?"

* * *

The kid looked terrible. They were pale and they were losing a great amount of blood. Their face was bruised and their eyes were closed. While Sans was kind of relieved that Frisk hadn't been absorbed by the machine after its destruction, he was freaking out. They looked _terrible_.

"frisk, c'mon pal." Sans said, shaking them lightly. "w-wake up. please?"

There was no response coming from Frisk.

"frisk, don't do this to me- i-i can't- i can't lose you, n-nobody can." Sans said. He could feel his left eye flaming. "frisk, _please_ -"

No answer. Frisk didn't move at all. Sans leaned a little to check if their heart was beating or if they were even breathing. Neither of these were happening.

"no, p-please-" Sans mumbled to himself. He started shaking Frisk more and said: "c-come on, kid, **wake up**!"

No answer.

Sans's eyes widened.  _wait. w-what if... oh, of course- **magic**._

Depending on the situation, monsters were able to heal anyone, even humans. He wasn't even sure if his magic would actually do something to an injured human, but he was desesperate. He wouldn't let his friend die. Sans's hands lightened and he put them on Frisk's bleeding abdomen.

_come on, come on-_

He stayed in that position for a while. Then he realized his magic was too weak for Frisk, specially when they were in that state. Sans started crying out of panic. He felt completely useless to them.

"frisk, please!" Sans screamed. "wake up already!!"

He stared at Frisk's face. Their eyes still closed, their face still bruised. They didn't move. His magic made no effect. Sans sobbed loudly, hugging the child tightly.

"no..." He whispered.

Suddenly, an ambulance siren could be heard and the short skeleton looked at the upcoming ambulance with a certain hope in his eyes. Maybe it wasn't too late, maybe Frisk would wake up, maybe they would be okay-

"you- y-you'll be okay, r-right?" Sans asked them, receiving no answer at all. "please..."

The ambulance stopped. Several paramedics ran out of the vehicle. Inside it were two stretchers and they were taken outside. Sans let Frisk go carefully and soon two of the paramedics laid them on the stretcher. Meanwhile, the other one had... someone on it. Sans couldn't see their face due to the paramedics in front of them. He caught a glimpse of black clothing, but... he didn't know them. The paramedics, along with the stretchers, went back to the ambulance. Sans looked inside of it, catching another glimpse of the stranger: their head was bald and white... Before he could see the rest of him, the paramedics closed the doors of the vehicle. They drove away fast, the siren echoing in the street while the crowd stared at it with concerned and shocked faces. Sans did the same, but he ran back to his brother, who stayed silent the whole time.

"c-come on, pap!" He said. "let's-"

Papyrus looked astonished and guilty. He stared at the floor. Sans sighed deeply, holding his long skeleton arm.

"come on, bro." Sans said. "d-don't worry, they- they will make sure frisk is alright, okay?"

Papyrus finally looked at him, heartbroken. He sighed and mumbled:

"O-OKAY... THEY WILL BE ALRIGHT. H-HOPEFULLY..."

Sans and Papyrus didn't run so that they wouldn't get worse than before; the magic didn't heal them completely yet and they didn't want to strain. The two of them ended up taking a bus to go to the hospital since the car had been busted. Speaking of that, Papyrus didn't even mention his car after the accident. He didn't even appear to care about the damage caused by the crash. That was actually surprising, considering how much Papyrus loved his car. His little brother acted so differently in the past few days... Sans felt responsible for that.

* * *

He felt something.

Something... warm.

A blanket - no, actually, two blankets.

He also felt his back aching a little, but it wasn't as bad as before.

**_HM...?_ **

Gaster's eyes slowly opened. He could see a bright, white light, suddenly reminding him of the bright tunnel of the portal - the one that had been destroyed after him and Frisk had attempted to escape the Void. With that memory, he jumped out of fear, but then he came to realize that the light wasn't the portal. It was a common mercury-vapor lamp in the ceiling. Gaster looked around, only to find himself in a hospital room with yellow walls and white floor. He was laying on a bed and covered by two blankets. He looked down, seeing that he wasn't wearing his black overcoat. Instead, he wore a baggy hospital gown. He looked at his hands. He... he wasn't melting anymore. His body wasn't turning into dust. He felt _complete_.

Except maybe for one thing...

...

Where was Frisk?

Gaster panicked. In the last time he had seen them, they were in an awful state. Were they in that same hospital? Were they okay? Or... or were they dead?! He couldn't just stay in his bed, he had to find his friend.

 _ **FRISK?!**_ He screamed, even though the room was empty.

Gaster jumped out of his bed, but he fell on the ground. His legs weren't cooperating, after spending years in a dimension where gravity didn't exist. He felt like he was a baby again... He crawled back to his bed so he could stand up. He breathed heavily and almost started to run when a human doctor entered the room. Gaster soon tripped again. The woman doctor gasped and helped him to get up.

"M-Mister, are you okay?" She asked, leading him to his bed so he could sit.

**_H-HAVE YOU SEEN THEM?_ **

"Who?"

_**F-FRISK! THE CHILD I WAS CARRYING BEFORE I- A-ARE THEY OKAY?!** _

"Sir, calm down! Do not worry, the child- uh, Frisk, they... they are alright. They are in another room after a surgery."

Gaster took a while to process the woman's response. Frisk was alright, they were in the same hospital. He soon sighed deeply in relief. He buried his face on his hands. He couldn't help but cry and sob.

 ** _T-THANK GOD...._** He mumbled.

"L... Lie down for a while, mister." The doctor said. "You still need to rest so your magic heals you."

Gaster nodded but he wouldn't stop crying. He lied on the bed and stopped sobbing. Instead, he cried quietly and stared at the ceiling.

"Do not worry." The woman repeated. "Frisk will soon be able to go home."

Gaster nodded quietly. He couldn't help but wonder how was Frisk at the moment. They would probably be unawake, considering they had been through a surgery. He just wanted to see them again, he wanted to make sure Frisk was okay.

 ** _CAN I SEE THEM AFTERWARDS?_** Gaster asked, looking at the doctor.

"Why, yes..." She didn't look very fond of the idea, but nodded. "But I will let you know when Frisk is available for visits, alright?"

**_ALRIGHT THEN. T... THANK YOU._ **

She gave him a small smile. He smiled in return.

* * *

"THIS IS TAKING TOO LONG..."

Sans and Papyrus were waiting to be called in the waiting room of the only hospital for humans and monsters in town. It had been a while and they were both getting impatient. Well, mostly Sans; he played with his fingers anxiously and he was frowning. Papyrus swore that he heard his brother _growl_... He was too intimidated to make Sans feel better. He could be really scary sometimes, it even looked like he would kill the people who worked in the hospital for taking too long to call the brothers.

"Sans and... Papyrus?"

The skeletons jumped off their seats and ran as fast as possible to the nurse who called them. She looked at them with a certain shock.

"i-is frisk okay?" Sans asked, softening his face.

"They are recovering from the surgery, but they are alright."

"CAN WE SEE THEM?"

"I... I am afraid you cannot see them yet. The doctors are still checking on them to see if there is anything wrong. I... I just wanted to let you know that Frisk will soon be able to go home, hopefully."

Papyrus sighed in relief, but he frowned a bit.

"You shall wait a little longer if you want to visit them." The woman said. "I will let you know when it is possible, alright?"

Papyrus nodded. Sans sighed deeply, but nodded, too. She left the two in the waiting room again. Papyrus glanced at his brother, who went back to the frowning face. The tall skeleton couldn't help but feel something bad under his spine. Then he... he noticed that Sans still had that burnt piece of rope.

"wait a little longer." Sans imitated the nurse, scoffing. He looked angry, yet he smiled. His voice darkened all of a sudden. Papyrus looked at him with concern, not knowing what to do with him.

The two found their seats occupied already, which angered Sans even more, but he took deep breaths and was able to calm down.

"man... we better call toriel." Sans said, out of nowhere.

"OH, OF COURSE!"

Papyrus felt very stupid. He had even forgotten about Toriel. The parent-teacher conference would obviously be over by the time they were in the hospital. He checked his phone, only to find it out of batteries. How great...

"DARN IT! IT'S OUT OF BATTERIES!" Papyrus said, groaning.

Sans looked at his phone... which was also out of batteries. He sighed.

"welp... i'll use a public telephone." He said. "oh, uh, i-i think you should stay here. if anyone calls us, at least you will already be here and you can see frisk."

Papyrus nodded, even though he didn't want to be alone in the waiting room. He didn't protest because Toriel _really_ needed to know what was going on.

"OKAY, I WILL BE WAITING HERE..." He said, soon murmuring: "... ALONE..."

"it'll be quick, okay? i won't leave you here for so long." Sans gave him a sad smile. "i'll be right back."

Sans glanced at Papyrus before leaving the waiting room. He softened out of nowhere... How strange... Well, Sans could be very weird sometimes, but Papyrus would always love his big brother. He walked around to find somewhere to sit. _All_ seats were occupied...

* * *

The cold breeze from outside gave Sans chills under his bones. He breathed heavily. Aside from wanting to call Toriel, he felt like he needed some air after everything that was going on. He didn't feel that relaxed because he was very concerned about Frisk, but going outside made him feel a little bit better.

Luckily, there was a payphone very near to him. Nobody was using it. Sans felt a little more relieved, but he couldn't help but feel bad for Toriel. He wondered if she was home or if she was looking for Sans and Papyrus, or even maybe Frisk themself. There were some coins in his pocket and inserted two of them. He dialed her phone number.

Ring...

Ring...

...

Nobody picked up.

Sans sighed, dialing her phone number once again.

...

No response...

_come on, tori..._

He tried again. Toriel didn't pick up. What was she up to? She always answered her phone. She wouldn't be at school at that time, right? It was very late and parent-teacher conferences didn't last that long.

"well... here goes nothing..." Sans said, dialing her phone number again after inserting more coins.

Nobody picked up...

"i give up." He said, sighing deeply.

He walked away, making his way back to the hospital's entrance. It was strangely quiet... well, it was almost midnight. It was just odd several people were inside the hospital, yet outside there wasn't anyone in the street, except maybe for a few humans who just walked around. Sans stared at the starry sky, breathing heavily again. He was actually feeling comfortable there. He liked being around people, but there were times he liked staying alone. He just needed to be sometimes.

But he remembered his brother. He didn't want to let him alone in the waiting room for so long, not when Papyrus was still feeling sad over the accident. He wouldn't say it, but Sans could see it in his eyes. With that, he entered the hospital. The waiting room was a complete chaos... He looked around, but he failed at finding Papyrus in the sea of people standing up.

"papyrus?" Sans called him.

"SANS! OVER HERE!"

He caught a glimpse of a orange-red glove in the middle of the crowd. Sans ran to the sea of people, finding his brother standing up.

"SO, WHAT DID SHE SAY?" Papyrus asked.

"she didn't pick up her phone, bro..." Sans sighed.

"OH..."

"n-nobody said anything else about the kid, right?"

Papyrus shook his head with a sad face. "I HOPE WE WILL SEE THEM SOON..."

Sans gave him a side hug. "me too."

The two stood up, staying silent the whole time, while everyone else babbled about several things. Sans just looked around, ready for that woman or someone else to call the brothers so they could finally see Frisk.

* * *

Almost an hour had passed... The waiting room was getting a bit emptier by the time and, thankfully, Sans and Papyrus found two seats. The big brother was getting utterly impatient. The hospital people were calling everyone else but the skeletons and it was getting annoying. Nobody said anything else about Frisk's state, and that concerned them even more. What if something bad had happened?

 _i swear, if i have to wait **five more minutes**... _ Sans thought, trying his best to remain calm.

"Sans and Papyrus?"

The two jumped out of their seats again, running to the same woman.

"You can now see them." She said with a small smile. "Follow me."

"finally..." Sans whispered. Papyrus sighed deeply.

* * *

"OH MY..."

The skeletons finally entered the room where Frisk was resting. They looked better than before, but... their skin was still pale and they weren't awake. However, Papyrus could see they were breathing normally.

"THANK GOODNESS..." Papyrus said. "T-THEY ARE OKAY!"

Sans nodded. He was so quiet... His white pupils were gone. His grip on the burnt rope tightened. His hands were shaking lightly. Papyrus sighed deeply, then gazing at the poor child. He approached the bed they were lying on.

"FRISK..." Papyrus whispered, touching their small hand.

The child's eyes wouldn't open. Papyrus teared up already and let the tears come out.

"OH, FRISK!" He said a bit louder. He soon contained himself when he remembered that he was in a hospital. "I... I'M SORRY..."

He could hear Sans sighing from behind.

* * *

Frisk was breathing.

They were alive.

Sans couldn't be any more relieved than he already was, but looking at that poor injured kid was heartbreaking, specially when it was all his fault. He stared at Frisk's bruised face. He couldn't help but feel even more guilty after remembering that the child had risked their life to save another one. Sans wanted to punch himself for not believing in them.

"sorry, kiddo..." Sans said. "i'm so sorry..."

Papyrus was too tall and he stood on his knees so he could stay close to Frisk. Sans didn't need to do that. He approached the bed and stood next to it, looking at the child while the regret dominated his mind.

 _i did this to them._ He thought.  _god, they... they could have **died**._

"OH, FRISK..." Papyrus mumbled, holding Frisk's hand.

It was still a bit hard to believe that Frisk was alive. When Sans had found the burnt rope and the destroyed machine... he thought Frisk would be gone forever. Turned out to be the opposite, which was good, but... despite the child surviving the accident, he would never forgive himself for letting them do something so dangerous.

Sans heard the door open. The same woman showed up.

"Oh, I... I have forgotten a detail." She said, sounding embarrassed. "The man who saved the child is out of coma already."

Sans blinked. He didn't remember anyone in the hospital mentioning him when he and Papyrus first spoke to the doctor and the nurses.

"who?" He asked.

"Oh, I really did not give you further details, did I..." She sighed, appearing to be facepalming herself mentally. "In any case, a man - a monster, actually - saved Frisk, somehow... He was almost dying, but, according to the monster doctors, he had determination and... he was able to prevent Frisk and himself from dying."

"WOW, HE'S A HERO!" Papyrus said, sounding proud of the stranger.

The woman nodded. "You do not know him, do you? He claimed to be a close friend of Frisk."

"uh, what's his name?"

"Oh, I..." She laughed nervously. "I... I forgot that I did not ask him... He does not even have any documents, to say the least..."

Sans and Papyrus looked at each other with confusion. How strange...

"well, huh... where's he?" Sans asked.

"He is in another room, in this floor. I can take you there, if you wish."

Papyrus nodded, despite looking very confused and suspicious about that friend of Frisk... who could it be? It was a _man_... a monster man... He didn't even have documents. It would be better to see who was the one who saved Frisk from death. Sans had a strange feeling about him...

"SURE THING!" Papyrus said. He sounded a bit excited.

"Well then, let's go."

Papyrus glanced at Frisk with a sad expression, but he quickly became excited to see the "hero". Sans didn't feel the same way. There was... something weird about that friend of Frisk. Sans had the feeling that... he knew him, for some reason? He shrugged, but the feeling wouldn't go away. The skeletons and the nurse left Frisk's room and they walked to the very end of the corridor. When they arrived, the woman opened the door and entered the stranger's room before the brothers.

"Mister?" She called him. "Some of Frisk's... friends would like to see you."

 ** _HM?_**  A yawn was heard. **_OH, FRIENDS-?_**

That voice.

Sans immediately froze where he stood. He lost his breath.

Could it be...?

"... _dad_?"


	15. Reunion

Gaster honestly couldn't believe he had finally returned from the Void. He felt like the real world was something _new_ to him. And something great, too. He had enjoyed very much to lay on the comfortable hospital bed and the warmth of the room. He didn't feel such comfort in **years**.

And then... he was standing right in front of his sons, Sans and Papyrus. The nurse watched everything with confusion, as she didn't know what was going on. Meanwhile, the skeletons looked at him with shock. Papyrus's jaw dropped, Sans's eyes were completely black. Gaster couldn't even breathe right.

They could _see_ him.

 ** _S... SANS...? P-PAPYRUS...?_** He said, also very astonished.

The skeletons approached him, both very hesitant. They probably couldn't believe their father had been alive the whole time. Well, who would? Gaster himself still didn't understand how he had been able to survive a grave accident with the portal machine. He was supposed to be **dead**.

Gaster stood up, almost tripping again. Papyrus almost ran to help him, but he was too shocked to do anything. Gaster couldn't blame him.

 ** _OH, SONS..._** Gaster said, his eyes wetting at the sight of the skeletons.

After staring for what it felt like forever, Papyrus approached his father. His arm was getting closer to him, and... Gaster could feel his son's hand. He could feel the warmth of his orange-red glove... He breathed heavily. Papyrus passed both of his hands all over Gaster's face, mostly the cracks on his head.

"D... DAD..." Papyrus whispered.

Gaster offered him a sad smile before bursting in tears. He let out a miserable laugh. Papyrus ended up doing the same and hugged his father tightly.

"OH, DAD!" Papyrus said, sobbing on his shoulder. "Y... YOU CAME BACK!"

Gaster continued laughing and caressed Papyrus's back, which was covered by his "battle body". His younger son had grown so much, he was almost taller than Gaster, which made him cry even more. The two stayed in the weeping hug for a long time. Gaster then glanced at Sans, who did nothing but stare at the two quietly. He didn't even... move.

 ** _SANS?_** Gaster called him.

Sans breathed heavily. He was too astonished to do anything. Gaster and Papyrus looked at him, not letting go of each other.

 ** _IT... IT'S ME, SANS._** Gaster said.  ** _I... I AM BACK._**

Sans sobbed and, all of a sudden, he ran to his father and brother to give them both the tightest hug ever. He buried his face on Gaster's stomach and sobbed very loudly.

 ** _HERE, HERE... I AM FINALLY BACK. I WILL NEVER LEAVE YOU AGAIN._** Gaster said, wrapping his arms around both of his sons.

He could hear Sans's muffled laughing.

"d-d-dad!" The short skeleton said.

* * *

It wasn't a dream.

It wasn't a nightmare.

It was real.

 _He was alive_.

Sans hadn't thought the theory of his father surviving was right. Turned out that, in the end, he had been absolutely right. He had been told so many times that he would have wasted his time over something impossible, but he wished to shove it on everyone else's faces.

"y-you... you really did come back..." Sans said, his face still buried on his father's body. He sniffled and laughed. "oh my god..."

His father was back...

... just like he had promised.

Gaster sighed deeply, letting go of his sons after staying in that tight family hug for what seemed to be forever. Sans looked at his father with pain. It hurted to see Gaster's face cracked like that. Sans could see in his eyes how much he had suffered during his imprisonment in the Void.

 ** _I AM SORRY._** He said.

"FOR WHAT?" Papyrus asked, confused.

 ** _... FOR EVERYTHING. I... I HAVE NOT SPENT TIME WITH YOU TWO BECAUSE OF MY WORK. I... I HAVE NOT GIVEN YOU ENOUGH AFFECTION._** Gaster sighed again.  ** _I SHOULD HAVE BEEN A BETTER FATHER._**

"DON'T SAY THAT, DAD! YOU'RE THE GREATEST FATHER EVER! YOU DID EVERYTHING FOR US!"

**_I... I BARELY EVEN SPENT TIME WITH YOU TWO. I THOUGHT... I THOUGHT THAT WORKING VERY HARD WOULD GIVE YOU EVERYTHING... BUT IT TURNED OUT THAT I HAVE NOT GIVEN YOU EVERYTHING; I... I WAS NOT THERE FOR YOU._ **

"DAD..."

**_I AM SO SORRY, BOYS... BUT I PROMISE THAT I WILL ALWAYS BE THERE FOR YOU, FROM NOW ON. AND I WILL NOT BREAK THIS PROMISE. NEVER AGAIN._**

Sans and Papyrus stared at him with tears on their eyes. Gaster blaming himself for everything was heartbreaking. Their father was brilliant. Not only as a parent, but also as a scientist. He may have not spent much time with his sons, but he had worked very hard to give them a good life. He had done quite good things for Sans and Papyrus, something that bad fathers would never be willing to do.

"YOU'RE THE BEST FATHER IN THE WHOLE WORLD!" Papyrus said, hugging Gaster again. "DON'T BE SORRY... WE UNDERSTAND."

Gaster sighed deeply, returning the hug.  ** _I LOVE YOU... I LOVE YOU SO MUCH..._**

"we love you too, dad." Sans smiled sadly, immediately joining the hug again.

"YOU ARE VERY GREAT." Papyrus said.

Gaster let out a sad chuckle.  ** _YOU ARE THE BEST THINGS TO EVER HAPPEN IN MY LIFE._**

They all laughed, cried and sobbed. The reunion of a broken family, never expected to happen... Sans felt like he was dreaming, when he clearly knew that it was all real. Finally, the "font" family was back together, and they would do everything to not fall apart ever again.

It all happened thanks to... Frisk.

Sans's eyes opened when he remembered the poor child. Frisk was responsible for Gaster's return. They were responsible for the family reunion. They... they were very crazy to do something so dangerous and crazy like that, but... in the end, they were truly a hero. They already were, after freeing monsters from the Underground, but they saved someone in _another dimension_.

Frisk was **extraordinary**. Sans could never ask for a better human friend.

"god, that kid is just great." He mumbled.

"YOU MEAN FRISK?"

Sans nodded. "yea..."

Gaster smiled sadly.  ** _THEY SAVED MY LIFE..._** Suddenly, his eyes widened and he said:  ** _WAIT! DID YOU SEE THEM ALREADY?_**

"they were unawake when we visited them. but don't worry, they're fine."

"YEAH! AND THEY MIGHT WAKE UP VERY SOON!"

Gaster sighed, relieved.  ** _I REALLY WANT TO SEE THEM. I ENDED UP SLEEPING FOR A WHILE..._**

"THEN LET'S GO TO THEIR ROOM! OH, WAIT... ARE YOU ALRIGHT NOW?"

**_I AM. THE MAGIC HAS HEALED ME. HOWEVER... I STILL CAN'T USE MY LEGS. I FEEL LIKE A BABY AGAIN..._ **

Gaster chuckled, but Sans could never think that the fact that his father didn't even know how to walk anymore was funny. It was depressing, actually... But he didn't say anything.

"WE CAN HELP YOU!" Papyrus said, offering his arms to help him.

Sans and Papyrus held Gaster's arms and they lead him the way to Frisk's room. The nurse left them alone after giving them a warm smile, despite not knowing what was happening.

"YOU'RE DOING GREAT, DAD!" Papyrus said, seeing how good Gaster was doing at walking. "YOU WILL SOON BE ABLE TO WALK AGAIN!"

Gaster smiled at him.  ** _THANK YOU._**

* * *

Some familiar voices could be heard in the middle of the darkness...

"they are a crazy kid..."

"THEY SCARED US TO DEATH..." A sigh was heard. "BUT WE SHOULD HAVE BELIEVED IN THEM."

Frisk slowly opened their eyes. Their vision was blurry and still dark. They weren't able to fully recognize the three shadows talking to them.

**_FRISK?_ **

"OH MY GOD! THEY- THEY ARE-?!"

"kid?!"

Finally, they recognized the three people: Sans, Papyrus and... **Gaster**. Papyrus was already crying tears of joy while Sans and Gaster looked at them with shock, without any tears on their faces.

"FRISK!!" Papyrus said, more tears falling from his eyes. He immediately hugged Frisk tightly. "THANK GOODNESS!!!"

Frisk was still feeling dizzy, but they returned the hug. They were very confused, they didn't even know where they were to begin with. The human looked around, seeing that the room they were in had yellow walls. They were laying on a big bed, and... they were wearing a hospital gown. Frisk then turned their gaze at Gaster with surprise. Was he really... right there?

 ** _OH, FRISK..._** Gaster said, sniffling.  ** _THANK YOU SO MUCH..._**

Frisk's eyes widened. "W-Wait... did... did I...?"

**_YOU SAVED ME, FRISK. I AM FINALLY BACK HOME._ **

Frisk wasn't dreaming. Their friend was right in front of them. Sans looked at him with a wide grin. Papyrus gazed at the two with tears of joy.

They really did it.

"O-Oh my god!" Frisk said, already crying, too. "Gaster, you- you are-!"

Gaster laughed sadly, hugging Frisk tightly. The child sobbed on his shoulder, gripping his... hospital gown. They had saved him for... for real. For some reason, they hadn't thought they would be able to save him, at least... not without... sacrificing their own life. Frisk knew that they... they could have died, but they had been more determined to save Gaster.

They were alive. Well, their belly was aching. They were in a hospital, they had been obviously injured, but they had made it without dying. And, most importantly, Gaster returned and he and his sons have finally reunited.

Frisk then let go of Gaster and gazed at him with joy.

 ** _I SHOULD HAVE NEVER ABANDONED YOU, FRISK..._** Gaster's smile faded a little.

"Hey, don't... don't worry about that, okay? I know how hard it must have been for you."

Gaster looked away with sadness and regret.

"It's okay, Gaster..." Frisk said. "I understand."

They pulled him for another tight hug.

"You're my best friend." They said. "I love you."

Gaster chuckled.  ** _I LOVE YOU, TOO._**

Frisk smiled, but their mood quickly changed when they noticed Sans was approaching them. The child soon recorded of the argument they had had with the skeleton, the things they had told him and done to him, such as stealing the portal machine and poking around his personal things... They felt bad, despite feeling proud of themselves after saving Gaster.

"S... Sans, I..." Frisk sighed deeply. "I'm sorry, I shouldn't have-"

Sans sobbed and tightened his arms around Frisk's body. They were a bit startled in the beginning, but they returned it when they realized that he wasn't mad at them anymore. He was _glad_ to see them.

"god, i'm so sorry, kid." Sans said. "i should've believed in you, you were right the whole time."

"It's okay..." Frisk sighed again. "I'm sorry for saying those things to you. I shouldn't have..."

"y'know... you were actually right about me." Sans chuckled sadly. "really, don't apologize for that."

"And sorry for stealing the machine... and destroying it..."

 ** _DON'T BLAME YOURSELF... PORTALS ARE VERY UNSTABLE, THEY CANNOT BE ACCESSED WITH SUCCESS._** Gaster said, trying to make them feel better about themself.

"WE'RE VERY THANKFUL, FRISK!" Papyrus smiled. "YOU SAVED OUR FATHER! I COULD NEVER FEEL ANY MORE PROUD!"

Frisk chuckled. Sans let go of them, giving them a smile.

"Aw, thanks, guys..." The child said.

"HOWEVER... YOU SHOULDN'T HAVE RUN AWAY." Papyrus's smile faded. He frowned a little. "AND... YOU DID SOMETHING **EXTREMELY** DANGEROUS."

Frisk looked down, embarrassed. "Sorry..."

"LOOK, JUST... JUST DON'T DO THAT EVER AGAIN, ALRIGHT? WE WERE WORRIED SICK!!"

"kid, if you ever do that again, you're gonna have a _bad_ time."

Frisk froze, looking at Sans with a certain fear. His pupils disappeared, leaving only a black void in his eyes. How could someone like him be so intimidating out of nowhere?

"nah, just messing with you, kiddo!" Sans said, his white pupils returning and a smile forming on his face. "no, but really, don't you ever do that again. i was really scared when i realized you were gone."

"I won't, I promise."

"GREAT! WELL, WE STILL NEED TO KNOW WHEN YOU WILL BE ABLE TO GO HOME. HOPEFULLY, IT WILL BE SOON!"

By hearing the word "home", Frisk immediately remembered of Toriel. They just realized that she wasn't in the room. Where was she? Did she even know what was going on? She... she probably didn't even know that they were in the hospital.

"Where's mom?" Frisk asked.

Papyrus's eyes widened. "AGH! HOW COULD I FORGET ABOUT LADY TORIEL?! SHE DOESN'T EVEN KNOW WE ARE HERE!!"

Frisk then remembered Alphys... The machine had been destroyed, and the explosion would have probably damaged her laboratory, or worse, her whole house. She wasn't there, either.

"Neither does Alphys, right...?" Frisk asked.

Papyrus shook his head. "SHE THOUGHT YOU... WELL, WHEN WE SAW HER, SHE FELT VERY GUILTY AND SHE RAN AWAY. SAME FOR UNDYNE."

Frisk didn't even know Undyne knew about what had happened. They wanted to see her, Alphys and Toriel again. They needed to give them some explanation... and an apology, obviously.

"I hope I can go home soon..." Frisk whispered.

They felt bad, but at least their friends were by their side. It was very warming to see Sans, Papyrus and Gaster together again. It had been worth the sacrifice, after all.

* * *

It actually didn't take much long for Frisk to recover from the surgery, at least not when they were already awake. They had spent a long time in coma, which allowed their state to get better, and the surgery had involved monster magic, which advanced the recovery. The child was soon able to go home with their friends. Outside the hospital, Sans attempted to call Toriel, but she didn't pick up her phone. He dialed the house's phone number, but that didn't work, either. The skeleton sighed deeply.

"man, i really don't know why she hasn't been answering her phone." He said. "i tried earlier, but the same happened."

"Then... then let's go home. It's all we can do, right?"

Sans looked very guilty, but he nodded. They all went home by taxi. In the way home, Frisk appreciated the view of the sky. It was already very late, but they couldn't tell what was the exact hour. The city was kind of empty at that time. It was all very quiet... yet it was a comfortable silence. They couldn't wait to see Toriel, to give her a tight hug and eat some of her delicious pies. They wanted to explain everything because she was the last one to know what had happened, and that would be very painful for her. Frisk still wondered where was she... she didn't answer her phone, neither the house's phone. Would she be home, or... would she be looking for them, Sans and Papyrus?

After a long time, since the hospital was very far away from their home, they finally arrived. Frisk breathed heavily, feeling a little nervous to face Toriel again. They would probably be grounded or something, but they deserved it.

Papyrus unlocked the house's door.

"HELLO? LADY TORIEL, WE ARE BACK!" He said.

There was no answer. The lights of the living room were turned off. It was strangely silent...

"She's not even here..." Frisk whispered, sighing.

At least that was what they thought.

They heard footsteps coming from upstairs. Toriel showed up with several tears on her face.

"F-Frisk?!" She said, gasping loudly.

She ran downstairs. Frisk laughed and sobbed, running to her, too. The two hugged each other tightly. Toriel's hugs were simply the best.

"M-My child, you- you are alright!" Toriel said. "Oh god- w-what happened? I-I looked everywhere for you! You wouldn't answer your phones and- and I went to the police station, b-but-"

Frisk sighed deeply. "I'm... I'm sorry for making you guys worried. I shouldn't have run away from home."

"W-Why would you do that?"

Frisk leaned their head towards Gaster's direction. Toriel looked at him with surprise. He was wearing his good old clothes, even though his black overcoat had been slightly torn after the destruction of the portal.

"Huh? W-Wait, I- I know you-" Toriel said, recognizing his appearence.

"He's W. D. Gaster, the Royal Scientist before Alphys. He... He was stuck in another dimension and... I rescued him."

Toriel looked at the child with shock. "W-Wait, is he- is he... Gaster, that... that friend of yours...?"

Frisk nodded.

"But... h-how did you...?"

Frisk looked down, feeling a little ashamed of explaining everything to their mother. "It's... It's a long story."

* * *

It had been hard to tell Toriel the whole story, but Sans and Papyrus were there to do it with Frisk, too. Gaster would say something once in a while, but he remained silent for most of the time. The goat had been really shocked during the explanation, especially in the part where Frisk had saved him and the portal had been destroyed. She was guilty for not answering her phone when Sans attempted to call her, but her cell phone had gone out of batteries and she had arrived home a bit before Frisk and the others arrived.

Frisk had done something very dangerous, but Toriel couldn't punish them. Not after everything they had been gone through. Besides, they did deserve an award for saving a brilliant scientist and reuniting a family; speaking of that, she had never known that Gaster was related to Sans and Papyrus, despite already knowing him. He had always been very reserved when it came to his personal life. She had only known about his wife, but not his sons.

After finishing the story, Toriel couldn't really say anything about it. She was too shocked, but she was glad that Frisk was alright.

"Am I in trouble?" Frisk asked.

"Oh no, clearly not, my child... just promise me you will never run away like that again, alright?"

Frisk nodded. "I promise."

"Good..." Toriel glanced at Gaster, who stared at the ground. "Despite everything, I... I am very proud of you, Frisk. You have saved this man and you have reunited a family." She smiled.

Frisk smiled in return, not saying anything. Toriel sighed deeply.

"We should all get some rest, shouldn't we?" She suggested. "It's very late, and after everything we have been gone through..."

Sans nodded. "yea..."

"Besides, after a surgery, it's best for Frisk to stay in bed for a while.

"Oh, doctor Gaster..." Toriel looked at the scientist. "Would you mind if you slept on the couch?"

 ** _OF COURSE NOT._** He answered.

"Well then... let's rest for a while, shall we?"

With everyone agreeing, Toriel carried Frisk to their room, while Sans, Papyrus and Gaster stayed in the living room. Frisk yawned. They must have been very tired... Toriel carefully lied them on their bed, covering them with the blanket. She sighed before kissing them on their forehead.

"Good night, my child." She said. "If you need everything, you can come over to me."

"Okay, mom. Good night." Frisk smiled, tired.

They closed their eyes, breathing deeply. Toriel didn't even leave their room. She felt like she shouldn't take her eyes off them, afraid they would run away again. She trusted them, but she was afraid of losing them again.

"I love you very much..." Toriel whispered, giving them a sad smile.

* * *

That couch really was comfortable...

Gaster was able to feel the couch. It was warm, but... he was having trouble at sleeping. Sans and Papyrus wanted to stay there with him, but he had told them they didn't have to worry about him.

He wasn't feeling alright at all. Not when that horrifying image of Frisk seriously injured was stuck in his mind.

He had been afraid of losing them. While he had been determined to save his friend, he had panicked. Frisk could have died. He had almost failed at protecting them from the destruction of the portal. That thought terrified him.

 **STOP THAT, THEY ARE OKAY. THEY ARE ALIVE, YOU... YOU DID SAVE THEM, IN THE END.** Gaster thought, taking deep breaths.

He didn't need to feel worried, did he? He had saved Frisk, they were home and they were alright, despite still needing to rest after the surgery.

**DON'T WORRY... JUST... JUST STOP THINKING ABOUT THIS. THEY ARE ALRIGHT.**

Gaster closed his eyes, breathing heavily. Slowly, he was leaving reality and arriving at the world of dreams...

* * *

He was in the middle of the darkness again. He couldn't tell if it was the Void, since the gravity was normal. Gaster looked around. Wasn't he home? Didn't he leave that awful dimension?

 ** _T... THIS DOESN'T MAKE SENSE._** He said.

He walked slowly. His body was shaking.

 ** _HELLO? S-SANS? PAPYRUS?_** Gaster called.  ** _F... FRISK?_**

But nobody came.

Gaster panicked. What was going on?

_It is all your fault._

Gaster jumped out of fear. The creepy voices were back.

_**W... WHAT THE...?** _

_Do not play like a fool. You know what I am talking about._

A light came out from... nowhere? It iluminated... something laying on the dark floor. Gaster approached it, his body shaking like crazy.

_Look at what you have done._

Gaster gasped loudly. Frisk was lying on the ground, unawake. They... they were in that injured state again, but... actually, they looked worse than before. A lot of blood came out from their body. Their eyes were open, but they were blank, lifeless.

 ** _FRISK!_** He screamed, falling on his knees and carefully carrying the child.

_They are dead because of you._

**_NO, I... I DID NOT FAIL! I SAVED THEM!_ **

_You did not. Look at them. Do they seem **okay** for you?_

Frisk wouldn't move. Gaster cried tears of pain and grief.

**_NO!_ **

_This is your fault._

_You are weak._

_You are useless._

**_The child risked their life for you, and you just throw them away like they are garbage._ **

_**NO!**_ Gaster yelled, sobbing loudly.

_YOUR FAULT_

_YOUR FAULT_

Gaster wouldn't stop crying. He hugged Frisk tightly. He suddenly felt his body vanish slowly.

**_NO... NO! FRISK!_ **

* * *

Sans's eyes opened in fear. He swore he heard his father scream from downstairs. Did something happen? Papyrus woke up with the scream, too.

"WHAT THE...?"

Loud sobs could be heard. Sans jumped out of his bed and rushed downstairs. His brother was right behind him.

"dad, what-"

Gaster was sitting on the couch. His eyes were purple, both flaming. Tears were falling, his body was shaking and he was panting. He looked **so** terrified.

"DAD! WHAT- WHAT HAPPENED?" Papyrus asked, running to his father and grabbing him by his shoulders.

Gaster didn't appear to notice them. Papyrus shaked him lightly.

"DAD, SAY SOMETHING!" He said.

The scientist gasped, jumping in fear as he noticed Papyrus's presence. He stared at him, suddenly becoming quiet.

**_P... P... PAPYRUS...?_ **

"WHAT.... WHAT HAPPENED, DAD?"

Gaster looked away, ashamed. He cried quietly, sniffling.

 ** _I- I THOUGHT... I..._** He mumbled, but he wasn't able to say anything about why he felt so scared.

"DID YOU HAVE A NIGHTMARE?"

Gaster took a while to answer with a nod.

 ** _IT... IT WAS SO REAL, I..._** He sniffled again.

"IT'S OKAY, DAD, WE... WE ARE HERE FOR YOU." Papyrus hugged him tightly.

Gaster took a deep breath.  ** _T... THANK GOD..._**

Sans sighed deeply. After they finished hugging, he and Papyrus sat on the couch with Gaster. They all stayed quiet for a while.

"WE CAN STAY HERE, IF YOU WANT." Papyrus said, trying to smile at his father.

Gaster nodded, not looking at either of them.

"don't worry, dad, you're okay." Sans said. "you're home now, there's nothing that can harm you now, okay?"

"YEAH! AND WE CAN BEAT UP THESE NIGHTMARES FOR YOU!"

Gaster let out a sad chuckle. He smiled weakly, still staying silent. Papyrus sighed, laying on his right shoulder and wrapping his arm around him.

"WE ARE HERE FOR YOU, DAD." Papyrus said, closing his eyes.

Sans lied on his father's arm, as he was too short to reach his other shoulder. He hugged him, too. Gaster was a bit startled. That nightmare should have been terrible... Sans knew how it was. He had nightmares and felt the same way, too. At least Papyrus was there for him.

Gaster breathed heavily, finally calming down, after a while. Sans closed his eyes, smiling.

* * *

Toriel only left Frisk's room to drink some water. She couldn't even sleep. Instead, she just watched Frisk sleep peacefully. She was a bit surprised that the child was even able to sleep, after everything... But she wouldn't complain. Frisk was alright and that was all that mattered.

She went downstairs, expecting to find Gaster sleeping on the couch. However... she found Sans and Papyrus sleeping with him. Gaster and Sans slept quietly, while Papyrus was snoring. Toriel smiled. That was an adorable scene. She realized she had forgotten to offer Gaster a blanket and she felt ashamed for that. Thus, she quickly made her way to her bedroom, picking a warm and long blanket for the family. She covered them with it. Then, she patted Sans's head, chuckling.

Before Toriel went to the kitchen, she glanced at Sans. She noticed he formed a smile on his face.

**Notes for the Chapter:**

> Wow... It's almost over... ;-; I had so much fun writing it...  
> Well, there's still one last chapter!
> 
> Thank you all for the kudos and comments! I love seeing how much you enjoy this story! :')


	16. Epilogue

Due to the accident, Frisk had ended up skipping school for a few days and they had stayed home through the whole day, not making an effort so that they could heal completely. Alphys and Undyne had been very relieved to hear that the human was alright, and the pair had even visited Frisk one day. Thankfully, the two of them were in good terms; Undyne had forgiven Alphys for letting Frisk enter the portal. The scientist had assured Frisk that they didn't need to worry about her house, as the explosion of the machine had only destroyed the laboratory. Alphys was currently living with Undyne until her house was reformed.

Speaking of her, she had begun a friendship with Gaster. The two would talk about science things, and that made Frisk happy. Because of Alphys, Gaster became an anime fan. He would occasionally watch it when possible. It turned out to be something very important to him, too... Papyrus wouldn't understand, but he liked seeing his father happy.

Gaster lived with his sons, Frisk and Toriel. He still slept on the couch, though, but he wouldn't complain. It was enough for him, considering that he hadn't felt such comfort in decades. He wouldn't throw his current life for anything in the world. However, he would still deal with nightmares and breakdowns now and then, and they could be very serious. Gaster would panic, he would think he was still trapped in the Void. Thankfully, he had the support from his family and they would always assure him that he was home. He probably would never fully recover from that traumatizing experience, but he was slowly moving on.

Back at school, Frisk's friends were very glad to see them again after they returned. Everyone had known about the accident, but not many details.

"Yo, dude!" Monster Kid said. "I've heard about the accident, you okay now?"

Frisk nodded.

"Good, good..." The monster sighed, smiling. "Well, so... would you like to play in recess?"

"Sure!" Frisk answered. They didn't remember the last time they had played with their friends ever since they had started to reject them due to their imaginary friend.

* * *

It was a nice Friday afternoon. School had just finished, yet Toriel still didn't show up. Thus, the child stayed there a little longer because of their friends. They would all ask them about their state and they would apologize about how rude they had acted with them because of their imaginary friend.

Speaking of their friend...

"So, huh," Monster Kid said, after everyone stopped apologizing and after Frisk assured them that it was okay. "you wanna come over my house tomorrow and-"

The monster couldn't finish the sentence when a tall figure approached. They shivered a little, but they soon calmed down when Frisk gave the man a wide, surprised smile.

"H-Hey!" Frisk said, giving him a hug. "I didn't know you were coming!"

**_TORIEL ASKED ME TO PICK YOU UP. SHE HAD SOME THINGS TO DO._**

The child looked behind, only to find Monster Kid and their other friends watching the scene with confusion.

"Oh, he... he is my friend, Gaster." Frisk said.

Monster Kid stared at him with shock.

"Woah! He's- wow!!" The monster said, not knowing the exact words to speak.

Several children of the school ran to them, gasping and whispering things. They all looked at Gaster with curiosity, as they had probably heard about Frisk's imaginary friend. Finding out that he was real for real would obviously come as a surprise for them.

The children became silent after a while, not asking anything about Gaster. Noticing that they wouldn't speak at all, Frisk told Monster Kid: "So I'll go to your house tomorrow! See ya!"

"S... See ya, dude!" Monster Kid answered, still distracted and surprised at Frisk's real friend.

Frisk held Gaster's hand and the two of them left the school. The children stared at them walking away.

* * *

**A few months later...**

The snow fell from the bright gray (almost white), cloudy sky. Schools were closed due to the winter break, and people were taking the day off. Children spent the day by staying outside. They would make snowmen, throw snowballs at each other or make snow angels on the ground. Frisk and their family were no exception. They were all in the garden, who was completely covered by the snow, except maybe for a few tall flowers which would survive the winter. Frisk made a snow angel while Toriel watched them doing so. The child then stood up to see how it looked. It was done fairly well. Toriel gave them a sign of approval.

"Well done." She said. smiling.

Frisk smiled back, but turned their gaze to another direction when they heard voices. Sans, Papyrus and Gaster were throwing snowballs at each other. Frisk chuckled, glad that they were having those sweet family moments.

After a rough "war", Gaster was victorious. Papyrus groaned and Sans fell on the ground, completely done.

 ** _I TOLD YOU I WAS GREAT AT THIS!_** The scientist said, cheerful.

"I DEMAND A REMATCH! THE GREAT PAPYRUS CANNOT BE DEFEATED IN A SNOWBALL WAR!!" Papyrus brushed the snow off his body. "I WILL DEFEAT YOU!!"

Sans took a while to stand up, yet he was laughing softly while Papyrus kept on saying how victorious he would be after defeating his father on a rematch. Gaster went along, teasing his sons by saying that he was the champion at Snowball War. Meanwhile, Frisk and Toriel watched them having a good time. The scene was very heart-warming.

"You really are very great, Frisk." She said. "You have reunited a family."

She looked at the child, holding Frisk's gloved hand. The child smiled.

"I am proud of you." Goat Mom smiled back.

Frisk gave her a tight hug. "I love you, mom."

Toriel chuckled lightly, patting their back. "I love you very much, my child."

* * *

They were finally having that time that Gaster had promised a long time ago. Sans honestly had never expected that his father would ever come back, even less the fact that they would play in the snow someday. Well, nobody else had believed that Gaster was alive, after all... Sans wouldn't say it, but he still felt bad for not believing in Frisk before. He should have listened to them instead of just getting mad and letting them do something dangerous to the point of almost _dying_...

He sighed deeply. He didn't want to be in a bad mood just yet. His father was there. His brother was there. They were all together, finally having that great time they all deserved. That was all that mattered, and nothing would ruin that precious moment.

Papyrus insisted on the rematch and they ended up starting the Snowball War all over again. Gaster was very skilled at it, winning them in a short period of time once again. Papyrus groaned in protest, as Gaster shoved his second victory on his sons' faces.

"NO!!" Papyrus whined. "I HAVE BEEN DEFEATED AGAIN!!"

The skeleton brothers were on the ground again, covered by the great amount of snowball thrown by their father. Gaster helped them to get up, offering them a smile.

 ** _YOU MAY NOT BEAT ME AT SNOWBALL WAR, PAPYRUS... BUT YOU CERTAINLY ARE THE BEST SNOWMAN BUILDER._** He said, pointing to the snowmen made by the three of them.

They analysed the three snowmen; Papyrus's was the best out of the them. Sans didn't make much effort, and his snowman turned into a mere pile of snow. Gaster's wasn't proportionally accurate.

 ** _YOU ARE VERY TALENTED, SON._** Gaster said, patting Papyrus's back. Sans offered his little brother a smile.

"THAT IS TRUE!" The tall skeleton formed a wide smile on his face. "I, THE GREAT PAPYRUS, AM THE _BEST_ SNOWMAN BUILDER TO EVER EXIST! NYEH HEH HEH!!"

Gaster chuckled and gave him a hug, both laughing. Sans watched them with joy until his brother pulled him to join the hug. Sans was initially surprised, which made him blush lightly.

"h-hey!" He said.

"IT'S HUG TIME, SANS! EVERYBODY NEEDS A HUG, AND SO DO YOU!"

Sans scoffed. He wasn't much of a hugger... well, he would hug the people he cared in certain circumstances, but he wasn't like his brother. Still, Sans chuckled and returned the hug, squeezing Gaster and Papyrus a little.

He loved them so much.

* * *

Gaster couldn't help but let out tears of joy as he tightened the hug a little more. Sans and Papyrus were the light of his life, and staying in the darkness of the Void had been the most painful experience he had ever been through. He would get very emotional by just remembering that, but his life had changed for the better and he still couldn't believe it. Of course, he wouldn't complain; he was living on the surface. He was able to see the real stars, to live among humans, to cherish freedom, to finally spend time with his sons.

_He was finally home._

**Notes for the Chapter:**

> Now it's finally over... ;v;  
> Thank you all for the support! I really appreciate it! :3c


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